A genome-wide Association study of the Count of Codeine prescriptions.

Opioid prescription records in existing electronic health record (EHR) databases are a potentially useful, high-fidelity data source for opioid use-related risk phenotyping in genetic analyses. Prescriptions for codeine derived from EHR records were used as targeting traits by screening 16 million patient-level medication records. Genome-wide association analyses were then conducted to identify genomic loci and candidate genes associated with different count patterns of codeine prescriptions. Both low- and high-prescription counts were captured by developing 8 types of phenotypes with selected ranges of prescription numbers to reflect potentially different levels of opioid risk severity. We identified one significant locus associated with low-count codeine prescriptions (1, 2 or 3 prescriptions), while up to 7 loci were identified for higher counts (≥ 4, ≥ 5, ≥6, or ≥ 7 prescriptions), with a strong overlap across different thresholds. We identified 9 significant genomic loci with all-count phenotype. Further, using the polygenic risk approach, we identified a significant correlation (Tau = 0.67, p = 0.01) between an externally derived polygenic risk score for opioid use disorder and numbers of codeine prescriptions. As a proof-of-concept study, our research provides a novel and generalizable phenotyping pipeline for the genomic study of opioid-related risk traits.

Post-Tonsillectomy Bleeding and Analgesic Use Before and After the FDA Boxed Warning Against Codeine.

OBJECTIVE: The aim of this study was to investigate the trends in post-tonsillectomy analgesic utility and incidence of post-tonsillectomy hemorrhage before and after the 2013 FDA Boxed Warning against codeine use after pediatric tonsillectomy. METHODS: A retrospective study was conducted using TriNetX. A search for patients up to 18 years from 2008 to 2022 within the US Collaborative Network identified 15,648,542 subjects. CPT and ICD-10 codes were used to identify children who experienced post-tonsillectomy hemorrhage within 14 days of a tonsillectomy. Analgesics given within 14 days of tonsillectomy were tabulated annually from 2008 to 2022, including codeine, ibuprofen, acetaminophen, oxycodone, ketorolac, and hydrocodone. Bleeding percentage and analgesic utility were grouped into events before and after 2013. RESULTS: Mean age at tonsillectomy was 5.6 years (SD = 3.0). Before 2013, the median percentage of children who experienced postoperative bleeding was 1.8% with 0.73% returning to the OR for bleeding control. After 2013, the median percentage of children who experienced postoperative bleeding was 2.4% (p = 0.029), and 0.99% returned to the OR (p = 0.008). Use of post-tonsillectomy codeine fell from 10.4% to 0.5% (p = 0.003) whereas ibuprofen rose from 2.0% to 63.9% (p = <0.001), acetaminophen from 42.8% to 77.2% (p = <0.001), ketorolac from 1.2% to 9.2% (p = <0.001), and oxycodone from 2.0% to 30.9% (p = <0.001). No change was detected in use of hydrocodone. CONCLUSION: Analgesics used post-tonsillectomy in children have changed since the FDA Boxed Warning against codeine. There has been a small but statistically significant increase in post-tonsillectomy bleeding. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:4783-4788, 2024.

Health Canada advisory impacts on the prevalence of oral codeine use in the Pediatric Canadian population: comparative study across provinces.

Health Canada (HC) has, since 2013, issued safety alerts restricting the use of codeine-containing drugs among breastfeeding women and children/adolescents under 18 years of age. These products are linked to breathing problems among ultra-rapid CYP2D6 metabolizers and early use of opioid can lead to future opioid misuse. Using a multi-province population-based cohort study, we estimate the impact of federal safety alerts on annual rates of codeine use in the Canadian pediatric population. We analyzed data from 8,156,948 children/adolescents in five Canadian provinces between 1996 and 2021, using a common protocol. Children/adolescents were categorized as: ≤ 12 years (children) or > 12 years (adolescents). We defined codeine exposure by ≥ 1 prescription filled for codeine alone or combined with other medications. For both age categories, we obtained province-specific codeine prescription filling rates per calendar year by dividing the number of children/adolescents with ≥ 1 codeine prescription filled by the number of person-time. Annual rates of codeine use per 1000 persons vary by province from 3.0 (Quebec) to 10.1 (Manitoba) in children, and from 5.5 to 51.3 in adolescents. After the 2013 HC advisory, exposure decreased in all provinces (adjusted level change from - 0.6 to - 18.4%) in children and from - 2.1 to - 17.9% in adolescents after the 2016 advisory. Annual rates declined over time in all provinces, following HC safety alerts specific to each of the two age categories.

Development and validation of a brief screening tool for over-the-counter codeine dependence.

BACKGROUND: Low-dose codeine is sold without a prescription in countries like the UK, Ireland, and South Africa. Due to misuse concerns, exploring pharmacy screening tools to identify those at risk and needing additional support is vital. OBJECTIVES: The study aims to develop and validate a brief screening tool that assesses the risk of codeine dependence with language appropriate for routine use in community pharmacies. METHOD: Scale development and validation occurred over two studies. In Study 1, scale item generation was based on structured analyses of psychosocial and pharmacy variables from frequent over-the-counter codeine consumers (N = 795). CFA was used to assess the cohesiveness of the resultant four-item Codeine Dependence Scale (CDS). ROC analyses were used to assess the performance of the CDS against risk cases identified by the Severity of Dependence Scale; identifying an optimal cut-off value of ≥2 as representing individuals at risk of codeine dependence. In Study 2, this CDS threshold was assessed against positive DSM-5 Opioid Use Disorder (OUD) cases related to codeine use assessed using the AUDADIS-IV. RESULTS: With a cut-off score of ≥2, the CDS has sensitivity and specificity of 76% and 48%, respectively, against a DSM-5 codeine-related OUD diagnosis using the AUDADIS-IV. For identification of any codeine-related OUD (as measured by the AUDADIS-IV) 15 months after baseline, the CDS achieved an overall correct classification rate of 52%; 72% for positive cases. CONCLUSIONS: The CDS exhibits reasonable cross-sectional and longitudinal sensitivity but low specificity, partly due to its brevity. However, the inclusive nature of the CDS is not a negative for application as a screening tool in a pharmacy setting as individual CDS items represent critical conversation points with a pharmacist, regardless of the screening outcome. The non-confronting nature of CDS items make the scale a viable option for pharmacy-based SBI in countries where codeine remains OTC.

Pholcodine and allergy to neuromuscular blocking agents: where are we and how did we get here?

Despite the purported link between pholcodine and neuromuscular blocking agent allergy, screening for prior pholcodine use offers no practical benefit to patients, and anaesthetists should continue to use a neuromuscular blocking agent where this is clinically indicated.

Exploring Perceptions About Paracetamol, Tramadol, and Codeine on Twitter Using Machine Learning: Quantitative and Qualitative Observational Study.

BACKGROUND: Paracetamol, codeine, and tramadol are commonly used to manage mild pain, and their availability without prescription or medical consultation raises concerns about potential opioid addiction. OBJECTIVE: This study aims to explore the perceptions and experiences of Twitter users concerning these drugs. METHODS: We analyzed the tweets in English or Spanish mentioning paracetamol, tramadol, or codeine posted between January 2019 and December 2020. Out of 152,056 tweets collected, 49,462 were excluded. The content was categorized using a codebook, distinguishing user types (patients, health care professionals, and institutions), and classifying medical content based on efficacy and adverse effects. Scientific accuracy and nonmedical content themes (commercial, economic, solidarity, and trivialization) were also assessed. A total of 1000 tweets for each drug were manually classified to train, test, and validate machine learning classifiers. RESULTS: Of classifiable tweets, 42,840 mentioned paracetamol and 42,131 mentioned weak opioids (tramadol or codeine). Patients accounted for 73.10% (60,771/83,129) of the tweets, while health care professionals and institutions received the highest like-tweet and tweet-retweet ratios. Medical content distribution significantly differed for each drug (P<.001). Nonmedical content dominated opioid tweets (23,871/32,307, 73.9%), while paracetamol tweets had a higher prevalence of medical content (33,943/50,822, 66.8%). Among medical content tweets, 80.8% (41,080/50,822) mentioned drug efficacy, with only 6.9% (3501/50,822) describing good or sufficient efficacy. Nonmedical content distribution also varied significantly among the different drugs (P<.001). CONCLUSIONS: Patients seeking relief from pain are highly interested in the effectiveness of drugs rather than potential side effects. Alarming trends include a significant number of tweets trivializing drug use and recreational purposes, along with a lack of awareness regarding side effects. Monitoring conversations related to analgesics on social media is essential due to common illegal web-based sales and purchases without prescriptions.

A software tool to adjust codeine dose based on CYP2D6 gene-pair polymorphisms and drug-drug interactions.

Codeine is metabolized by the CYP2D6 enzyme, and individuals with certain genetic variations of the CYP2D6 gene may metabolize codeine differently, leading to variable efficacy and toxicity. Drug-drug interactions can also affect the metabolism of codeine. A tool to adjust codeine dose based on these factors does not currently exist. Healthcare providers should use their clinical judgment and reference different established dosing guidelines to determine the appropriate dose of codeine for individual patients. The study provides a tool that assists prescribers in adjusting codeine dose based on CYP2D6 gene-pair polymorphisms and drug-drug interactions. Highlighted is the need to consider pharmacogenetics and drug-drug interactions when determining the appropriate dosing of codeine and provide a framework for implementing individualized dosing based on these factors.

Cytochrome P450-2D6 activity in people with codeine use disorder.

Compound-analgesics containing codeine (CACC) have been a common source of codeine for people seeking opioid replacement therapy (ORT) for codeine use disorder (CUD). Our previous work demonstrated no relationship between pre-treatment CACC and ORT buprenorphine doses; we hypothesised that CYP2D6 activity would partially account for this disconnection. One hundred six participants with CUD were compared to a published population sample of 5408 Australian patients. Mean age of participants with CUD at treatment entry was 35 years, with mean 6.1 years duration of CUD. Mean codeine dose was 660 mg/day (range 40-2700 mg). Mean calculated CYP2D6 activity scores were significantly higher in the codeine group (CUD 1.65 + 0.63 vs. Gen pop 1.39 + 0.65, Wilcoxon W = 347,001, p < 0.001). Pre-treatment CACC dose weakly predicted sublingual buprenorphine doses overall; there was a stronger relationship within ultrarapid metabolisers. While normal and ultrarapid metabolisers of codeine were more likely to have a diagnosis of CUD, poor or intermediate CYP2D6 metaboliser status may protect against CUD.

L-Arginine abrogates maternal and pre-pubertal codeine exposure-induced impaired spermatogenesis and sperm quality by modulating the levels of mRNA encoding spermatogenic genes.

Introduction: Although, codeine has been demonstrated to lower sperm quality; the effects of maternal and prepubertal codeine exposure on male offspring is yet to be reported. In addition, the effect of arginine on codeine-induced decline in sperm quality has not been explored. This study investigated the impact of maternal and prepubertal codeine exposure on spermatogenesis and sperm quality in F1 male Wistar rats to study the effect that codeine may have during recreational use in humans. Also, the effect of arginine supplementation on codeine-induced alteration in spermatogenesis and sperm quality was evaluated. Methods: Female rats were treated with either 0.5 ml distilled water or codeine orally for eight weeks, and then mated with male rats (female:male, 2:1). The F1 male offsprings of both cohorts were weaned at 3 weeks old and administered distilled water, codeine, arginine, or codeine with arginine orally for eight weeks. Results: Prepubertal codeine exposure in rats whose dams (female parents) were exposed to codeine delayed puberty and reduced the weight at puberty. Prepubertal codeine exposure exacerbated maternal codeine exposure-induced reduced total and daily spermatid production, sperm count, sperm motility, and normal sperm form, as well as impaired sperm plasma membrane integrity and increased not intact acrosome and damaged sperm DNA integrity. These perturbations were accompanied by a decrease in mRNA levels encoding spermatogenic genes, testicular testosterone and androgen receptor (AR) concentrations, and upregulation of sperm 8-hydroxydeoxyguanosine (8OHdG). Prepubertal arginine supplementation mitigated codeine-induced alterations. Discussion: This study provides novel experimental evidence that maternal and prepubertal codeine exposure reprogramed spermatogenesis and sperm quality of male FI generation by decreasing mRNA levels encoding spermatogenic genes and AR via oxidative stress-mediated signaling, which was abrogated by prepubertal arginine supplementation.

Trends in adverse drug reactions related to oral weak opioid analgesics in therapeutic use in adults: A 10-year French vigilances retrospective study.

AIM: To describe the symptoms, patient demographics, and trends over time of adverse drug reactions (ADRs) related to weak opioid analgesics reported to the French vigilance networks. METHODS: Retrospective study of data from French Poison Control Centers and Pharmacovigilance Centers databases of weak opioid analgesics-related ADRs cases, with high causality score, in adults, in therapeutic analgesic use, without co-exposure, between 2011 and 2020. RESULTS: The number of cases was 388 in the Poisonings database and 155 in the Pharmacovigilance database; ratio of the number of these cases to all reported cases during the study period was 0.02% and 0.03%, respectively. Tramadol was most often involved (74% and 56.1%, respectively), followed by codeine (26% and 38.7%, respectively). There was no significant variation in the number of cases reported. Cases most often involved young adults (median age: 40 years) and mostly women (76%). Gastrointestinal symptoms were mostly reported (80% and 65%, respectively) as described in the Summary of Products Characteristics. Patterns of ADRs were comparable in both databases, except for codeine-associated acute pancreatitis and anaphylaxis that were reported in the Pharmacovigilance database. No fatality was observed. Severity was more often observed in the Pharmacovigilance database (30%) than in the Poisonings database (moderate toxicity: 7%). CONCLUSION: ADRs mostly occurred among young women using tramadol, without significant variation in the number of reported cases over time. Serious ADRs were more frequently reported to the Pharmacovigilance database, particularly for codeine. Women seemed to be at greater risk of ADRs.

Prescription of oxycodone versus codeine after childbirth and risk of persistent opioid use: a population-based cohort study.

BACKGROUND: Oxycodone is increasingly prescribed for postpartum analgesia in lieu of codeine owing to concerns regarding the neonatal safety of codeine during lactation. We examined whether initiation of oxycodone after delivery was associated with an increased risk of persistent opioid use relative to initiation of codeine. METHODS: We conducted a population-based cohort study of people who filled a prescription for either codeine or oxycodone within 7 days of discharge from hospital after delivery between Sept. 1, 2012, and June 30, 2020. The primary outcome was persistent opioid use, defined as 1 or more additional prescriptions for an opioid within 90 days of the first postpartum prescription and 1 or more additional prescriptions in the 91 to 365 days thereafter. We used inverse probability of treatment weighting to assess the risk of persistent postpartum opioid use, comparing people who initiated oxycodone with those who initiated codeine. RESULTS: Over the 8-year study period, we identified 70 607 people who filled an opioid prescription within 7 days of discharge from hospital: 21 308 (30.2%) received codeine and 49 299 (69.8%) oxycodone. Compared with people who filled a prescription for codeine, receipt of oxycodone was not associated with persistent opioid use (relative risk [RR] 1.04, 95% confidence interval [CI] 0.91-1.20). We found an association between a prescription for oxycodone and persistent use after vaginal delivery (RR 1.63, 95% CI 1.31-2.03), but not after cesarean delivery (RR 0.85, 95% CI 0.73-1.00). INTERPRETATION: Initiation of oxycodone (v. codeine) was not associated with an increased risk of persistent opioid use, except after vaginal delivery.

Analgesic effect of oral paracetamol 1000 mg/ibuprofen 400 mg, paracetamol 1000 mg/codeine 60 mg, paracetamol 1000 mg/ibuprofen 400 mg/codeine 60 mg, or placebo on acute postoperative pain: a single-dose, randomized, and double-blind study.

PURPOSE: Combining analgesics with different mechanisms of action may increase the analgesic efficacy. The multidimensional pharmacodynamic profiles of ibuprofen 400 mg/paracetamol 1000 mg, ibuprofen 400 mg/paracetamol 1000 mg/codeine 60 mg, and paracetamol 1000 mg/codeine 60 mg and placebo were compared. METHODS: A randomized, double-blind, placebo-controlled, parallel-group, single-centre, outpatient, and single-dose study used 200 patients of both sexes and homogenous ethnicity after third molar surgery (mean age 24 years, range 19-30 years). Primary outcome was sum pain intensity over 6 h (SPI). Secondary outcomes were time to analgesic onset, duration of analgesia, time to rescue drug intake, number of patients taking rescue drug, sum pain intensity difference (SPID), maximum pain intensity difference, time to maximum pain intensity difference, number needed to treat, prevent remedication and harm values, adverse effects, and patient-reported outcome measure (PROM). RESULTS: Analgesia following ibuprofen and paracetamol combination with or without codeine was comparable. Both were better than paracetamol combined with codeine. Secondary variables supported this finding. Post hoc analysis of SPI and SPID revealed a sex/drug interaction trend in the codeine-containing groups where females experienced less analgesia. PROM showed a significant sex/drug interaction in the paracetamol and codeine group, but not in the other codeine-containing group. Especially females reported known and mild side effects in the codeine-containing groups. CONCLUSION: Codeine added to ibuprofen/paracetamol does not seem to add analgesia in a sex-mixed study population. Sex may be a confounding factor when testing weak opioid analgesics such as codeine. PROM seems to be more sensitive than traditional outcome measures. TRIAL REGISTRATION: ClinicalTrials.gov June 2009 NCT00921700.

Pharmacokinetics and effects of codeine in combination with acetaminophen on thermal nociception in horses.

Codeine and acetaminophen in combination have proven to be an effective analgesic treatment for moderate-to-severe and postoperative pain in humans. Studies have demonstrated that codeine and acetaminophen, when administered as sole agents, are well tolerated by horses. In the current study, we hypothesized that administration of the combination of codeine and acetaminophen would result in a significant thermal antinociceptive effect compared with administration of either alone. Six horses were administered oral doses of codeine (1.2 mg/kg), acetaminophen (20 mg/kg), and codeine plus acetaminophen (1.2 mg/kg codeine and 6-6.4 mg/kg acetaminophen) in a three-way balanced crossover design. Plasma samples were collected, concentrations of drug and metabolites determined via liquid chromatography-mass spectrometry, and pharmacokinetic analyses were performed. Pharmacodynamic outcomes, including effect on thermal thresholds, were assessed. Codeine Cmax and AUC were significantly different between the codeine and combination group. There was considerable inter-individual variation in the pharmacokinetic parameters for codeine, acetaminophen, and their metabolites in horses. All treatments were well tolerated with minimal significant adverse effects. An increase in the thermal threshold was noted at 1.5 and 2 h, from 15 min through 6 h and 0.5, 1, 1.5, and 3 h in the codeine, acetaminophen, and combination groups, respectively.

Reduced gastrointestinal-related hospitalisation costs following rescheduling of over-the-counter codeine-containing compound analgesics in Australia: results of a single hospital audit in South Australia.

BACKGROUND: Codeine-containing compound analgesics (CCCAs) are associated with dependence and, when taken in excess, significant risks of harm. A previous audit showed significant costs related to admissions for gastrointestinal (GI) complications of CCCA. Based on this and other evidence of harm, the Australian Therapeutic Goods Administration changed CCCAs to prescription only in 2018. AIMS: We aimed to identify the costs associated with codeine-related GI complications and whether the schedule change in 2018 led to a reduced clinical and financial strain on the health care system. METHODS: We conducted an audit of GI admissions and associated costs of CCCAs at a tertiary teaching hospital in Adelaide between 2016 and 2020. Patients were grouped by 2-year time periods before (group 1) and following (group 2) schedule change. Costs for the index presentation were multiplied for subsequent presentations. Costs and outcomes were compared for groups (standard statistics; P value < 0.05 significant.) RESULTS: Three hundred forty patients (group 1, n = 164; group 2, n = 119) were identified, with the majority of these admitted due to nonsteroidal anti-inflammatory drugs (NSAIDs) only. For CCCAs (NSAID-containing), the same patients were admitted repeatedly with a reduction from 31 to eight admissions (P = 0.005), following rescheduling. The total cost of CCCA admissions was reduced from AU$ 561 691 for group 1 to AU$ 261 764 for group 2 (P < 0.001). CONCLUSIONS: Australian rescheduling of CCCAs in 2018 resulted in a reduction in hospital admissions and costs related to GI complications. The cost savings, even in a single hospital department, were substantial.