A case of naltrexone-induced acute eosinophilic pneumonia.

Acute eosinophilic pneumonia (AEP) is a rare cause of acute respiratory failure. Clinical presentations can range from dyspnoea, fever and cough, to rapidly progressive and potentially fulminant respiratory failure. While its exact cause is often unknown, associations with inhalational injuries and exposures to new medications have been described.We report a case of a middle-aged, non-smoking man with a history of alcohol use disorder. He presented with 4 days of shortness of breath that started hours after taking injectable naltrexone (Vivitrol). The patient had rapidly worsening hypoxaemia, necessitating emergent bronchoscopy with transbronchial biopsies and bronchoalveolar lavage which showed 66% eosinophils. The patient was intubated for the procedure and unable to get extubated due to worsening hypoxaemic respiratory failure with high fractional inspired oxygen requirements. Chest radiograph showed worsening lung infiltrates and with a high index of suspicion for AEP, he was started empirically on methylprednisolone. He had rapid improvement in his respiratory status and was extubated on day 5 of admission then discharged on day 8. Histopathological examination confirmed acute/subacute eosinophilic pneumonia. A 3-week post-discharge follow-up chest radiograph confirmed the full resolution of pulmonary infiltrates.Naltrexone-induced AEP is rare, with only six other cases reported in the literature. Careful history taking and prompt evaluation for AEP are important given the potential for rapid progression to acute hypoxic respiratory failure and the excellent response to steroid treatment.

Pharmacological prevention and treatment of opioid-induced constipation in cancer patients: A systematic review and meta-analysis.

BACKGROUND: Cancer-related pain often requires opioid treatment with opioid-induced constipation (OIC) as its most frequent gastrointestinal side-effect. Both for prevention and treatment of OIC osmotic (e.g. polyethylene glycol) and stimulant (e.g. bisacodyl) laxatives are widely used. Newer drugs such as the peripherally acting µ-opioid receptor antagonists (PAMORAs) and naloxone in a fixed combination with oxycodone have become available for the management of OIC. This systematic review and meta-analysis aims to give an overview of the scientific evidence on pharmacological strategies for the prevention and treatment of OIC in cancer patients. METHODS: A systematic search in PubMed, Embase, Web of Science and the Cochrane Library was completed from inception up to 22 October 2022. Randomized and non-randomized studies were systematically selected. Bowel function and adverse drug events were assessed. RESULTS: Twenty trials (prevention: five RCTs and three cohort studies; treatment: ten RCTs and two comparative cohort studies) were included in the review. Regarding the prevention of OIC, three RCTs compared laxatives with other laxatives, finding no clear differences in effectivity of the laxatives used. One cohort study showed a significant benefit of magnesium oxide compared with no laxative. One RCT found a significant benefit for the PAMORA naldemedine compared with magnesium oxide. Preventive use of oxycodone/naloxone did not show a significant difference in two out of three other studies compared to oxycodone or fentanyl. A meta-analysis was not possible. Regarding the treatment of OIC, two RCTs compared laxatives, of which one RCT found that polyethylene glycol was significantly more effective than sennosides. Seven studies compared an opioid antagonist (naloxone, methylnaltrexone or naldemedine) with placebo and three studies compared different dosages of opioid antagonists. These studies with opioid antagonists were used for the meta-analysis. Oxycodone/naloxone showed a significant improvement in Bowel Function Index compared to oxycodone with laxatives (MD -13.68; 95 % CI -18.38 to -8.98; I2 = 58 %). Adverse drug event rates were similar amongst both groups, except for nausea in favour of oxycodone/naloxone (RR 0.51; 95 % CI 0.31-0.83; I2 = 0 %). Naldemedine (NAL) and methylnaltrexone (MNTX) demonstrated significantly higher response rates compared to placebo (NAL: RR 2.07, 95 % CI 1.64-2.61, I2 = 0 %; MNTX: RR 3.83, 95 % CI 2.81-5.22, I2 = 0 %). With regard to adverse events, abdominal pain was more present in treatment with methylnaltrexone and diarrhea was significantly more present in treatment with naldemedine. Different dosages of methylnaltrexone were not significantly different with regard to both efficacy and adverse drug event rates. CONCLUSIONS: Magnesium oxide and naldemedine are most likely effective for prevention of OIC in cancer patients. Naloxone in a fixed combination with oxycodone, naldemedine and methylnaltrexone effectively treat OIC in cancer patients with acceptable adverse events. However, their effect has not been compared to standard (osmotic and stimulant) laxatives. More studies comparing standard laxatives with each other and with opioid antagonists are necessary before recommendations for clinical practice can be made.

The safety and efficacy of methylnaltrexone in pediatric oncology patients: A single center experience.

INTRODUCTION: Peripherally acting µ-opioid receptor antagonists (PAMORAs) are used in the treatment of opioid induced constipation without impacting the actions of opioid analgesics. Subcutaneous methylnaltrexone was one of the first PAMORAs approved in April 2008 for the treatment of opioid induced constipation in adult patients. The safety and effectiveness of methylnaltrexone has not been established in pediatric patients. In this study, the use of subcutaneous methylnaltrexone in pediatric patients is analyzed and reviewed. The primary outcome is occurrence of a bowel movement within 24 h after methylnaltrexone (MNTX) administration and the number of bowel movements following treatment with methylnaltrexone. Secondary outcomes include safety in this patient cohort. METHODS: This is a retrospective study of 79 pediatric patients with opioid induced constipation. Patients were administered methylnaltrexone during their inpatient stay. Data on bowel activity after methylnaltrexone was obtained from the hospital information system. RESULTS: Out of the 79 patients who received methylnaltrexone, there were seven patients from whom data could not be analyzed. Of the 72 patients whose data was available, 38% (N = 27) were documented as having a bowel movement, 62% (N = 45) did not have a bowel movement. Reported adverse events were minimal with nausea (N = 3), vomiting (N = 1), and flatulence (N = 6). CONCLUSION: Methylnaltrexone appears safe in the pediatric population and produces bowel movements in more than a third of pediatric patients. It is a feasible and safe option for opioid induced constipation in pediatric patients.

Efficacy and safety of naldemedine treatment for opioid-induced constipation in gastrointestinal cancer: a retrospective analysis.

BACKGROUND: Gastrointestinal cancers are one of the most common cancer cases worldwide. Cancer treatment is multidisciplinary, which includes opioid pain management. Opioid analgesics cause opioid-induced constipation (OIC) with the onset of effect. Naldemedine, a peripheral opioid receptor antagonist, is an OIC-modifying agent, but no focused efficacy and safety analysis has been conducted for its use in gastrointestinal cancers. METHODS: We retrospectively evaluated patients with gastrointestinal cancer treated with naldemedine at ten institutions in Japan from June 2017 to August 2019. Patients with gastrointestinal cancer who initiated treatment with opioids during hospitalization and were treated with naldemedine for the first time were included in the study. The gastrointestinal cancer types included were esophageal, gastric, small bowel, and colorectal cancers. We assessed the defecation frequency before and after the initiation of naldemedine use. Responders were defined as patients who defecated three or more times/week, with an increase from the baseline of one or more bowel movements/week over seven days after starting naldemedine. RESULTS: Thirty-three patients were observed for one week before and after starting naldemedine. Twenty-one patients had an increase in defecation frequency of at least three times per week or at least once per week above the baseline. The response rate was 63.6% [95% confidence interval (CI): 46.6-77.9%]. The median number of bowel movements for a week before and after the initiation of naldemedine treatment was 3 (range, 0-13) and 7 (range, 1-39), respectively, in the overall population (n=33), with a significant increase in defecation frequency following naldemedine administration (Wilcoxon signed rank test, P<0.005). Diarrhea was the predominant gastrointestinal symptom, with 13 (39.4%) patients experiencing grade 1 and none experiencing grade 3 or grade 4 adverse events. The frequency of other grade 1 adverse events was low abdominal pain in two patients, nausea in two patients, and anorexia in one patient, without any grade 2-4 adverse events. CONCLUSIONS: The results of the study suggest that naldemedine is effective and safe in clinical practice for gastrointestinal cancer treatment.

No pain, no strain: Targin® mitigates pain and constipation following spinal cord injury.

BACKGROUND: Opioids effectively reduce chronic pain, but present significant side effects including opioid-induced constipation. Oxycodone/naloxone decreases pain and constipation in cancer patients, however its effect on spinal cord injury population remains understudied. METHODS: We assessed whether oxycodone/naloxone reduces pain, constipation, and severity of autonomic dysreflexia in an individual with spinal cord injury. A 55-year-old male with C5 lesion presented with chief complaint of chronic pain received 5/2.5 mg and 20/10 mg oxycodone/naloxone for 6 and 2 weeks, respectively. RESULTS: Oxycodone/naloxone improved pain, bowel function, and autonomic dysreflexia severity. INTERPRETATION: Oxycodone/naloxone was effective in managing chronic pain and constipation in the studied case.

One-year efficacy and safety of naloxegol on symptoms and quality of life related to opioid-induced constipation in patients with cancer: KYONAL study.

OBJECTIVES: Naloxegol is a peripherally acting µ-opioid receptor antagonist (PAMORA) for treatment of opioid-induced constipation (OIC). The main objective was to analyse the long-term efficacy, quality of life (QOL) and safety of naloxegol in patients with cancer in a real-world study. METHODS: This one-year prospective study included patients older than 18 years, with active oncological disease who were under treatment with opioids for pain control and Karnofsky≥50 and OIC with inadequate response to treatment with laxative (s). All the patients received treatment with naloxegol according to clinical criteria. The main efficacy objectives were measured by the patient assessment of constipation QOL questionnaire (PAC-QOL), the PAC symptoms (PAC-SYM), the response rate at day 15, and months 1-3-6-12, and global QOL (EuroQoL-5D-5L). RESULTS: A total of 126 patients (58.7% males) with a mean age of 61.5 years (95% CI 59.4 to 63.7) were included. PAC-SYM and PAC-QOL total score and all their dimensions improved from baseline (p<0.0001). At 12 months, 77.8% of the patients were responders to naloxegol treatment. Global QOL was conserved from baseline. A total of 28 adverse reactions, mainly gastrointestinal were observed in 15.1% of the patients (19/126), being 75% (21) mild, 17.9% (5) moderate and 7.1% (2) severe. Most adverse reactions (67.9%) appeared the first 15 days of treatment. CONCLUSION: The results of this first long-term and real-world-data study in patients with cancer, showed the sustained efficacy and safety of naloxegol for the treatment of OIC in this group of patients.

Response Rates to Methylnaltrexone in Hospitalized Cancer Patients.

Context: Methylnaltrexone is a peripherally-acting mu-opioid receptor antagonist studied in both cancer and non-cancer patients with opioid-induced constipation (OIC), but mostly in the outpatient setting. For adult hospitalized cancer patients with OIC, its effectiveness is unknown. Objectives: Describe the efficacy of methylnaltrexone for OIC in the inpatient setting, defined as bowel movement (BM) within 24 hours of methylnaltrexone administration. Methods: We performed a single-center, retrospective chart review of all hospitalized, adult patients with a cancer diagnosis who received methylnaltrexone from the palliative care team between January 1st, 2012 and July 1st, 2019. Results: We identified 194 patients. The mean age was 59, 50.5% were male and 88% were white. 192 patients (98%) received the 8 mg dose subcutaneously. The median oral morphine equivalent (OME) was 135 mg (IQR 70-354 mg). 45% (95% confidence interval, 38-53%) had a BM within 24 hours. Higher OME was correlated with successful BM, with a response in 93% (86/92) of patients receiving ≥150 OME and 2% (2/102) of patients receiving <150 OME (P < .0001). Prior laxative use did not predict response at 24 hours whether these were osmotic laxatives (40.7% vs 47.1%, P = .52), stimulant laxatives (45.7% vs 45.2%, P > .99), or stool softeners (44.7% vs 46.1%, P = .89). Conclusion: Methylnaltrexone has a high response rate when used as treatment for OIC in hospitalized adult cancer patients, especially for patients taking ≥150 OME.

Factors associated with non-response to naldemedine for opioid-induced constipation in cancer patients: A subgroup analysis.

BACKGROUND: Opioid-induced constipation (OIC) is one of the most common adverse events of opioid therapy and can severely reduce quality of life (QOL). Naldemedine is the orally available peripheral-acting µ-opioid receptor antagonist approved for OIC treatment. However in daily clinical practice, some cancer patients show insufficient control of OIC even while receiving naldemedine. OBJECTIVE: To identify factors associated with non-response to naldemedine in cancer patients. METHODS: This study retrospectively analyzed 127 cancer patients prescribed naldemedine at Seirei Hamamatsu General Hospital in Japan between November 2016 and June 2021. For the regression analysis of factors associated with OIC, variables were extracted manually from electronic medical records. Naldemedine had been prescribed by the attending physician after the presence of OIC had been defined with reference to Rome IV diagnostic criteria. Naldemedine was evaluated as "effective" in cases where the number of defecations increased at least once in the first 3 days after starting naldemedine. Multivariate logistic regression analysis was performed to identify factors associated with non-response to naldemedine. The data used were from the group of patients who received naldemedine in our previous study. RESULTS: Factors significantly associated with non-response to naldemedine included chemotherapy with taxanes within 1 month of evaluation of naldemedine effect (odds ratio [OR] = 0.063; 95% confidence interval [CI] = 0.007-0.568), and addition of or switching to naldemedine due to insufficient efficacy of prior laxatives (OR = 0.352, 95% CI = 0.129-0.966). CONCLUSION: The identification of factors associated with non-response to naldemedine prescribed for OIC may help improve QOL among cancer patients.

Mu-opioid antagonists for opioid-induced bowel dysfunction in people with cancer and people receiving palliative care.

BACKGROUND: Opioid-induced bowel dysfunction (OIBD) is characterised by constipation, incomplete evacuation, bloating, and gastric reflux. It is one of the major adverse events (AEs) of treatment for pain in cancer and palliative care, resulting in increased morbidity and reduced quality of life. This review is a partial update of a 2008 review, and critiques as previous update (2018) trials only for people with cancer and people receiving palliative care. OBJECTIVES: To assess for OIBD in people with cancer and people receiving palliative care the effectiveness and safety of mu-opioid antagonists (MOAs) versus different doses of MOAs, alternative pharmacological/non-pharmacological interventions, placebo, or no treatment. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, CINAHL, and Web of Science (December 2021), clinical trial registries and regulatory websites. We sought contact with MOA manufacturers for further data. SELECTION CRITERIA: Randomised controlled trials (RCTs) assessing the effectiveness and safety of MOAs for OIBD in people with cancer and people at a palliative stage irrespective of the type of terminal disease. DATA COLLECTION AND ANALYSIS: Two review authors assessed risk of bias and extracted data. The appropriateness of combining data from the trials depended upon sufficient homogeneity across trials. Our primary outcomes were laxation response, effect on analgesia, and AEs. We assessed the certainty of evidence using GRADE and created summary of findings tables. MAIN RESULTS: We included 10 studies (two new trials) randomising in-total 1343 adults with cancer irrespective of stage, or at palliative care stage of any disease. The MOAs were oral naldemedine and naloxone (alone or in combination with oxycodone), and subcutaneous methylnaltrexone. The trials compared MOAs with placebo, MOAs at different doses, or in combination with other drugs. Two trials of naldemedine and three of naloxone with oxycodone were in people with cancer irrespective of disease stage. The trial on naloxone alone was in people with advanced cancer. Four trials on methylnaltrexone were in palliative care where most participants had advanced cancer. All trials were vulnerable to biases; most commonly, blinding of the outcome assessor was not reported.  Oral naldemedine versus placebo Risk (i.e. chance) of spontaneous laxations in the medium term (over two weeks) for naldemedine was over threefold greater risk ratio (RR) 2.00, 95% confidence interval (CI) 1.59 to 2.52, 2 trials, 418 participants, I² = 0%. Number needed to treat for an additional beneficial outcome (NNTB) 3, 95% CI 3 to 4; moderate-certainty evidence). Earlier risk of spontaneous laxations and patient assessment of bowel change was not reported. Very low-certainty evidence showed naldemedine had little to no effect on opioid withdrawal symptoms. There was little to no difference in the risk of serious (non-fatal) AEs (RR 3.34, 95% CI 0.85 to 13.15: low-certainty evidence). Over double the risk of AEs (non-serious) reported with naldemedine (moderate-certainty evidence). Low-dose oral naldemedine versus higher dose Risk of spontaneous laxations was lower for the lower dose (medium term, 0.1 mg versus 0.4 mg: RR 0.69, 95% CI 0.53 to 0.89, 1 trial, 111 participants (low-certainty evidence)). Earlier risk of spontaneous laxations and patient assessment of bowel change not reported. Low-certainty evidence showed little to no difference on opioid withdrawal symptoms (0.1 mg versus 0.4 mg mean difference (MD) -0.30, 95% CI -0.85 to 0.25), and occurrences of serious AEs (0.1 mg versus 0.4 mg RR 0.25, 95% CI 0.03 to 2.17). Low-certainty evidence showed little to no difference on non-serious AEs. Oral naloxone versus placebo Risk of spontaneous laxations and AEs not reported. Little to no difference in pain intensity (very low-certainty evidence). Full data not given. The trial reported that no serious AEs occurred. Oral naloxone + oxycodone versus oxycodone Risk of spontaneous laxations within 24 hours and in the medium term not reported. Low-certainty evidence showed naloxone with oxycodone reduced the risk of opioid withdrawal symptoms. There was little to no difference in the risk of serious (non-fatal) AEs (RR 0.68, 95% CI 0.44 to 1.06), 3 trials, 362 participants, I² = 55%: very low-certainty evidence). There was little to no difference in risk of AEs (low-certainty evidence).  Subcutaneous methylnaltrexone versus placebo Risk of spontaneous laxations within 24 hours with methylnaltrexone was fourfold greater than placebo (RR 2.97, 95% CI 2.13 to 4.13. 2 trials, 287 participants, I² = 31%. NNTB 3, 95% CI 2 to 3; low-certainty evidence). Risk of spontaneous laxations in the medium term was over tenfold greater with methylnaltrexone (RR 8.15, 95% CI 4.76 to 13.95, 2 trials, 305 participants, I² = 47%. NNTB 2, 95% CI 2 to 2; moderate-certainty evidence). Low-certainty evidence showed methylnaltrexone reduced the risk of opioid withdrawal symptoms, and did not increase risk of a serious AE (RR 0.59, 95% CI 0.38 to 0.93. I² = 0%; 2 trials, 364 participants). The risk of AEs was higher for methylnaltrexone (low-certainty evidence). Lower-dose subcutaneous methylnaltrexone versus higher dose There was little to no difference in risk of spontaneous laxations in the medium-term (1 mg versus 5 mg or greater: RR 2.91, 95% CI 0.82 to 10.39; 1 trial, 26 participants very low-certainty evidence), or in patient assessment of improvement in bowel status (RR 0.98, 95% CI 0.71 to 1.35, 1 trial, 102 participants; low-certainty evidence). Medium-term assessment of spontaneous laxations and serious AEs not reported. There was little to no difference in symptoms of opioid withdrawal (MD -0.25, 95% CI -0.84 to 0.34, 1 trial, 102 participants) or occurrence of AEs (low-certainty evidence). AUTHORS' CONCLUSIONS: This update's findings for naldemedine and naloxone with oxycodone have been strengthened with two new trials, but conclusions have not changed. Moderate-certainty evidence for oral naldemedine on risk of spontaneous laxations and non-serious AEs suggests in people with cancer that naldemedine may improve bowel function over two weeks and increase the risk of AEs. There was low-certainty evidence on serious AEs. Moderate-certainty evidence for methylnaltrexone on spontaneous laxations over two weeks suggests subcutaneous methylnaltrexone may improve bowel function in people receiving palliative care, but certainty of evidence for AEs was low. More trials are needed, more evaluation of AEs, outcomes patients rate as important, and in children.

A retrospective study of the efficacy and safety of naldemedine for opioid-induced constipation in thoracic cancer patients.

BACKGROUND: We conducted a multicenter, retrospective study on the efficacy and safety of naldemedine in thoracic cancer patients using opioids in clinical practice. METHODS: We retrospectively evaluated thoracic cancer patients treated with naldemedine at 10 institutions in Japan. Clinical data of patients administered naldemedine between June 2017 and August 2019 were extracted from electronic medical records. Inclusion criteria were as follows: (i) patients hospitalized for at least seven days before and after naldemedine administration, and (ii) those whose frequency of defecation was entered in the medical records. RESULTS: Forty patients were analyzed, and defecation frequency was observed for at least seven days before and after naldemedine administration. The response rate was 65.0% (95% CI: 50.2%-79.7%). The number of defecations increased significantly after naldemedine administration in the overall population, as well as among only those who defecated <3 times/week before naldemedine administration, and those that were administered ≥30 mg/day of morphine equivalent. Diarrhea was the most common adverse event in all grades, occurring in 11 patients (27.5%), of which 9 (81.8%) were grade 1 or 2. None of the patients experienced grade 4 or higher adverse events. CONCLUSION: The efficacy and safety of naldemedine for thoracic cancer patients in clinical practice were comparable with those of prospective studies, which suggest that naldemedine may be effective and feasible for most thoracic cancer patients.

Perioperative subcutaneous methylnaltrexone does not enhance gastrointestinal recovery after posterior short-segment spinal arthrodesis surgery: a randomized controlled trial.

BACKGROUND CONTEXT: Postoperative ileus is a major barrier to gastrointestinal recovery following surgery. Opioid analgesics likely play an important causative role, particularly in spinal or orthopedic surgeries not involving bowel manipulation. Methylnaltrexone, a peripherally-acting µ-opioid receptor antagonist, is a potential prophylactic treatment. PURPOSE: To assess the influence of perioperative subcutaneous methylnaltrexone administration on gastrointestinal recovery following short-segment lumbar arthrodesis surgeries. DESIGN: This is a randomized, double-blind, controlled trial. PATIENT SAMPLE: Eligible patients undergoing posterior short-segment lumbar arthrodesis surgeries at a single institution between February 2019 and April 2021 were enrolled in this study. OUTCOME MEASURES: The primary outcome measure was time-to-first bowel movement. Secondary outcome measures included time-to-discharge/discharge eligibility. Exploratory outcome measures included daily postoperative opioid consumption and pain scores. METHODS: In this study, eligible patients were enrolled to receive either methylnaltrexone or placebo perioperatively. Time-to-bowel movement, time-to-discharge/discharge eligibility, intra and postoperative analgesic administration, and pain scores were recorded and compared. RESULTS: Eighty two patients in total were enrolled; 41 to the methylnaltrexone and 41 to the placebo group. Both groups were similar in their baseline characteristics. There was no difference in median (range) time-to-bowel movement between the 2 groups [61.8 hours (35.7-93.6) versus 50.7 hours (17.8-110.8), p = .391]. There was also no difference in time-to-discharge/discharge eligibility [105.0 hours (81.0 - 201.3) versus 90.7 (77.5 - 184.5), p=.784]. Finally, there were no differences in either postoperative opioid consumption or numeric rating scores for back, leg, or abdominal pain on postoperative days 0 to 4 (p>.05). CONCLUSIONS: Methylnaltrexone did not accelerate gastrointestinal recovery and did not affect opioid consumption or pain scores following short-segment spinal surgery as compared to placebo. Additional studies will be needed to identify effective opioid receptor antagonist dosing regimens for patients undergoing either short- or long-segment spinal arthrodesis procedures.

The Efficacy and Safety of Methylnaltrexone for the Treatment of Postoperative Ileus.

BACKGROUND: Postoperative ileus (POI) is a surgical complication resulting in increased morbidity and length of stay (LOS). Usual care for POI includes bowel rest and gastric decompression. It has been questioned if methylnaltrexone (MNTX), a peripheral opioid antagonist, could be used as treatment for POI. The purpose of this study was to determine if MNTX is effective and safe for POI treatment. METHODS: This single-center, retrospective cohort study included patients ⩾ 18 years with a POI. Patients with acute colonic pseudo-obstruction, small bowel obstruction, and gastrointestinal malignancy were excluded. The intervention was MNTX administration. The primary outcome was time to ileus resolution. Secondary outcomes included LOS, duration of nasogastric tube, total parenteral nutrition requirement, and incidence of gastrointestinal perforations. RESULTS: 110 patients were included in the analysis; 28 received MNTX. Time to ileus resolution was 9.9 days for the MNTX group and 11.4 days for the control group (P = .38). Duration of gastric decompression was 4.6 days for the MNTX group and 4.2 days for the control group (P = .71). Length of stay was 19.9 days for the MNTX group and 19.7 days for the control group (P = .96). The percentage of TPN requirement was 17.9% in the MNTX group and 22.0% in the control group (P = .65). No gastrointestinal perforations were observed in either group. CONCLUSION: For the treatment of POI, MNTX did not significantly reduce time to resolution of ileus, LOS, duration of gastric decompression, or TPN requirements. However, no gastrointestinal perforations were seen, indicating that MNTX may be safely used in these patients.

Naldemedine-induced opioid withdrawal syndrome with severe psychiatric symptoms in an advanced cervical cancer patient without brain metastasis.

OBJECTIVE: Naldemedine, an oral peripheral µ-opioid receptor antagonist, was developed for the treatment of constipation, a side effect of opioid use. Naldemedine is not generally recognized as causing opioid withdrawal in which associated symptoms affecting the central nervous system. METHOD: From the series of cancer patients undergoing symptom management, we report a case treated with naldemedine for constipation in relation to the use of opioids for cancer pain and who displayed severe psychological symptoms associated with withdrawal immediately after the use of naldemedine. RESULTS: The patient was a 36-year-old woman diagnosed with cervical cancer Stage IIB, PS3. When the patient, who was using oxycodone hydrochloride hydrate (80 mg/day) for ileal pain, was started on naldemedine for constipation, she complained of sweating after just 5 min and hallucinations after 1 h. The patient also displayed physical/behavioral abnormalities such as diarrhea and hyperactivity, and psychological abnormalities such as aggression toward staff.Despite the psychiatric symptoms worsening over time, there were no abnormalities in terms of blood biochemical data, and no brain metastasis was observed on MRI. Based on the Clinical Opiate Withdrawal Scale, these symptoms were judged to indicate opioid withdrawal. Naldemedine was discontinued due to naldemedine-related opioid withdrawal syndrome and, thereafter, the psychiatric symptoms diminished, with no recurrence of similar symptoms observed to date. SIGNIFICANCE OF RESULTS: If mental and behavioral abnormalities occur in patients receiving naldemedine, it is necessary to consider the possibility of opioid withdrawal syndrome as a differential diagnosis.

Potential Therapeutic Benefit of Low Dose Naltrexone in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Role of Transient Receptor Potential Melastatin 3 Ion Channels in Pathophysiology and Treatment.

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a debilitating multi-systemic chronic condition of unknown aetiology classified as an immune dysfunction syndrome and neurological disorder. The discovery of the widely expressed Transient Receptor Potential Melastatin 3 (TRPM3) as a nociceptor channel substantially targeted by certain opioid receptors, and its implication in calcium (Ca2+)-dependent Natural Killer (NK) cell immune functions has raised the possibility that TRPM3 may be pharmacologically targeted to treat characteristic symptoms of ME/CFS. Naltrexone hydrochloride (NTX) acts as an antagonist to the mu (µ)-opioid receptor thus negating its inhibitory function on TRPM3. Based on the benefits reported by patients on their symptoms, low dose NTX (LDN, 3.0-5.0 mg/day) treatment seems to offer some potential benefit suggesting that its effect may be targeted towards the pathomechanism of ME/CFS. As there is no literature confirming the efficacy of LDN for ME/CFS patients in vitro, this study investigates the potential therapeutic effect of LDN in ME/CFS patients. TRPM3 ion channel activity was measured after modulation with Pregnenolone sulfate (PregS) and ononetin in NK cells on 9 ME/CFS patients taking LDN and 9 age- and sex-matched healthy controls using whole-cell patch-clamp technique. We report that ME/CFS patients taking LDN have restored TRPM3-like ionic currents in NK cells. Small ionic currents with a typical TRPM3-like outward rectification were measured after application of PregS, a TRPM3-agonist, in NK cells from patients taking LDN. Additionally, PregS-evoked ionic currents through TRPM3 were significantly modulated by ononetin, a TRPM3-antagonist, in NK cells from ME/CFS patients taking LDN. These data support the hypothesis that LDN may have potential as a treatment for ME/CFS by characterising the underlying regulatory mechanisms of LDN treatment involving TRPM3 and opioid receptors in NK cells. Finally, this study may serve for the repurpose of marketed drugs, as well as support the approval of prospective randomized clinical studies on the role and dose of NTX in treating ME/CFS patients.

The role of spinal inhibitory neuroreceptors in the antihyperalgesic effect of warm water immersion therapy.

OBJECTIVE: Warm water immersion therapy (WWIT) has been widely used in the treatment of various clinical conditions, with analgesic and anti-inflammatory effects. However, its mechanism of action has not been fully investigated. The present study analyzed the role of spinal inhibitory neuroreceptors in the antihyperalgesic effect of WWIT in an experimental model of inflammatory pain. METHODS: Mice were injected with complete Freund's adjuvant (CFA; intraplantar [i.pl.]). Paw withdrawal frequency to mechanical stimuli (von Frey test) was used to determine: (1) the effect of intrathecal (i.t.) preadministration of naloxone (a non-selective opioid receptor antagonist; 5 µg/5 µl), (2); AM281 (a selective cannabinoid receptor type 1 [CB1] antagonist; 2 µg/5 µl), (3); and 1,3-dipropyl-8-cyclopentylxanthine (DPCPX; a selective adenosine A1 receptor antagonist; 10 nmol/5 µl), on the antihyperalgesic (pain-relieving) effect of WWIT against CFA-induced hyperalgesia. RESULTS: Intrathecal naloxone, AM281, and DPCPX significantly prevented the antihyperalgesic effect of WWIT. This study suggests the involvement of spinal (central) receptors in the antihyperalgesic effect of WWIT in a model of inflammatory pain. CONCLUSIONS: Taken together, these results suggest that opioid, CB1, and A1 spinal receptors might contribute to the pain-relieving effect of WWIT.

Acute opioid withdrawal syndrome from naloxone/naloxegol interaction.

Naloxegol is a new peripherally acting mu-opioid receptor antagonist to treat opioid-induced constipation with supposedly no effect on opioid analgesia. We present a patient with cancer-related pain who developed acute opioid withdrawal symptoms due to an interaction between the opioid antagonist naloxone and naloxegol. He was treated with oxycodone sustained release because of poor pain control. For opioid-related constipation, he had been receiving naloxegol. He complained about worsening pain and constipation and oxycodone was switched to oxycodone/naloxone. Shortly after intake, he experienced acute severe agitation, anxiety, sweating, tachycardia, disorientation and yawning without improvement after intravenous midazolam. Only after intravenous morphine administration, symptoms were controlled. He was switched back to the previous oxycodone dose without naloxone, with naloxegol being maintained. In the light of this case we suggest to avoid the use of naloxone and naloxegol in combination, or at least, to use it with extreme caution and monitorisation of tolerance.

[Recommendations about the Use of Psychotropic Medications during the COVID-19 Pandemic]. / Recomendações sobre a Utilização de Fármacos Psicotrópicos durante a Pandemia COVID-19.

INTRODUCTION: The COVID-19 pandemic is a particularly relevant threat to mentally ill patients, and it constitutes a new challenge for health care providers. To the best of our knowledge, there is not any embracing published review about the use of psychotropic drugs during the COVID-19 pandemic. MATERIALS AND METHODS: Non-systematic literature review. A search in the PubMed database was performed, with the terms 'psychotropic drugs', 'COVID-19', 'psychiatry' and 'pandemic'. Consensus and clinical guidelines about psychotropic drugs and COVID-19 approach, published by scientific societies, governmental entities and drug regulatory agencies were included. RESULTS AND DISCUSSION: We present the recommendations about the use of psychotropic drugs during the COVID-19 pandemic, in the outpatient and inpatient settings. The treatment of affective bipolar disorder and schizophrenia have now added increased difficulties. Some psychotropic drugs interfere with the pathophysiology of the novel coronavirus infection and they could interact with the drugs used in the treatment of COVID-19. Some patients will need pharmacological interventions due to the presence of delirium. Smoking cessation changes the serum levels of some psychotropic drugs and may influence their use. CONCLUSION: The COVID-19 pandemic has created new challenges in clinical practice. Psychiatric patients are a vulnerable population and often a careful clinical, laboratorial and electrocardiographic evaluation may be needed, particularly in those diagnosed with COVID-19. The regular treatment of mentally ill patients with COVID-19 presents increased complexity.

Introdução: A pandemia de COVID-19 constitui uma ameaça particularmente relevante para os portadores de doença mental e um novo desafio para os profissionais que os acompanham. Até à data, tanto quanto sabemos, não existe qualquer revisão abrangente publicada relativamente à utilização de fármacos psicotrópicos durante a pandemia COVID-19. Material e Métodos: Revisão não sistemática da literatura. A pesquisa na PubMed foi realizada com os termos 'psychotropic drugs', 'COVID-19', 'psychiatry' e 'pandemic'. Foram incluídos os consensos e as normas publicadas pelas sociedades científicas, entidades governamentais e agências regulamentares de medicamentos. Resultados e Discussão: Apresentam-se recomendações relativamente à utilização de psicofármacos durante a pandemia COVID-19, em contexto de ambulatório e de internamento. O tratamento da perturbação afetiva bipolar e da esquizofrenia tem agora dificuldades acrescidas. Alguns psicofármacos interferem com os mecanismos fisiopatológicos envolvidos na infeção pelo novo coronavírus e têm interações com os fármacos utilizados no tratamento da COVID-19. Em doentes com COVID-19 e com delirium, a utilização de psicofármacos poderá ser necessária. A cessação tabágica altera os níveis séricos de alguns psicofármacos e pode condicionar a sua utilização. Conclusão: A pandemia de COVID-19 coloca novos desafios na prática clínica. Os doentes psiquiátricos constituem uma população vulnerável, sendo frequentemente necessária uma avaliação clínica, laboratorial e eletrocardiográfica cuidadosa, naqueles com o diagnóstico de COVID-19. Os doentes mentais com COVID-19 apresentam uma complexidade acrescida na gestão da sua terapêutica habitual.

Comparison of buprenorphine and methadone in the management of maternal opioid use disorder in full term pregnancies.

Objectives To compare pregnancy outcomes with medication assisted treatment using. methadone or buprenorphine in term mothers with opioid use disorder. Methods A cohort of women receiving medication assisted treatment with either methadone or buprenorphine were identified from delivery records over a 10-year period. Women were excluded with delivery <37 weeks, multiple gestations, or a known anomalous fetus. Maternal demographics, medications, mode of delivery, birthweight, newborn length of stay, and neonatal abstinence syndrome were extracted. The study was IRB approved and a p-value of <0.05 was significant. Results There were 260 women, 140 (53.8%) with methadone use and 120 (46.2%) with buprenorphine use. Groups were similar for maternal age, race, parity, homeless rate, tobacco use, mode of delivery and incidence of neonatal abstinence syndrome. The methadone group had a lower mean newborn birthweight (2874±459 g) and a greater incidence of low birth weight (11.4%) than the buprenorphine group (3282±452 g; p<0.001 and 2.5%; p=0.006). The incidence of neonatal abstinence syndrome was similar between groups (97% methadone vs. 92.5% buprenorphine; p=0.08). The methadone group had a longer newborn length of stay (11.4+7.4 days) and more newborn treatment with morphine (44.6%) than the buprenorphine group (8.2+4.4 days; p<0.001 and 24.2%; p<0.001). Maternal methadone use was an independent predictor for a newborn length of hospital stay >7 days (OR 3.61; 95% confidence interval 1.32-9.86; p=0.01). Conclusions Medication assisted treatment favors buprenorphine use when compared to. methadone with an increased birthweight, reduced need for newborn treatment, and a shorter newborn length of stay in term infants.

Screening for Unhealthy Drug Use: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force.

Importance: Illicit drug use is among the most common causes of preventable morbidity and mortality in the US. Objective: To systematically review the literature on screening and interventions for drug use to inform the US Preventive Services Task Force. Data Sources: MEDLINE, PubMed, PsycINFO, Embase, and Cochrane Central Register of Controlled Trials through September 18, 2018; literature surveillance through September 21, 2019. Study Selection: Test accuracy studies to detect drug misuse and randomized clinical trials of screening and interventions to reduce drug use. Data Extraction and Synthesis: Critical appraisal and data abstraction by 2 reviewers and random-effects meta-analyses. Main Outcomes and Measures: Sensitivity, specificity, drug use and other health, social, and legal outcomes. Results: Ninety-nine studies (N = 84 206) were included. Twenty-eight studies (n = 65 720) addressed drug screening accuracy. Among adults, sensitivity and specificity of screening tools for detecting unhealthy drug use ranged from 0.71 to 0.94 and 0.87 to 0.97, respectively. Interventions to reduce drug use were evaluated in 52 trials (n = 15 659) of psychosocial interventions, 7 trials (n = 1109) of opioid agonist therapy, and 13 trials (n = 1718) of naltrexone. Psychosocial interventions were associated with increased likelihood of drug use abstinence (15 trials, n = 3636; relative risk [RR], 1.60 [95% CI, 1.24 to 2.13]; absolute risk difference [ARD], 9% [95% CI, 5% to 15%]) and reduced number of drug use days (19 trials, n = 5085; mean difference, -0.49 day in the last 7 days [95% CI, -0.85 to -0.13]) vs no psychosocial intervention at 3- to 4-month follow-up. In treatment-seeking populations, opioid agonist therapy and naltrexone were associated with decreased risk of drug use relapse (4 trials, n = 567; RR, 0.75 [95% CI, 0.59 to 0.82]; ARD, -35% [95% CI, -67% to -3%] and 12 trials, n = 1599; RR, 0.73 [95% CI, 0.62 to 0.85]; ARD, -18% [95% CI, -26% to -10%], respectively) vs placebo or no medication. While evidence on harms was limited, it indicated no increased risk of serious adverse events. Conclusions and Relevance: Several screening instruments with acceptable sensitivity and specificity are available to screen for drug use, although there is no direct evidence on the benefits or harms of screening. Pharmacotherapy and psychosocial interventions are effective at improving drug use outcomes, but evidence of effectiveness remains primarily derived from trials conducted in treatment-seeking populations.

Screening for Unhealthy Drug Use: US Preventive Services Task Force Recommendation Statement.

IMPORTANCE: An estimated 12% of adults 18 years or older and 8% of adolescents aged 12 to 17 years report unhealthy use of prescription or illegal drugs in the US. OBJECTIVE: To update its 2008 recommendation, the USPSTF commissioned reviews of the evidence on screening by asking questions about drug use and interventions for unhealthy drug use in adults and adolescents. POPULATION: This recommendation statement applies to adults 18 years or older, including pregnant and postpartum persons, and adolescents aged 12 to 17 years in primary care settings. This statement does not apply to adolescents or adults who have a currently diagnosed drug use disorder or are currently undergoing or have been referred for drug use treatment. This statement applies to settings and populations for which services for accurate diagnosis, effective treatment, and appropriate care can be offered or referred. EVIDENCE ASSESSMENT: In adults, the USPSTF concludes with moderate certainty that screening by asking questions about unhealthy drug use has moderate net benefit when services for accurate diagnosis of unhealthy drug use or drug use disorders, effective treatment, and appropriate care can be offered or referred. In adolescents, because of the lack of evidence, the USPSTF concludes that the benefits and harms of screening for unhealthy drug use are uncertain and that the balance of benefits and harms cannot be determined. RECOMMENDATION: The USPSTF recommends screening by asking questions about unhealthy drug use in adults 18 years or older. Screening should be implemented when services for accurate diagnosis, effective treatment, and appropriate care can be offered or referred. (Screening refers to asking questions about unhealthy drug use, not testing biological specimens.) (B recommendation) The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of screening for unhealthy drug use in adolescents. (I statement).