Clinical validation of a fast-acting acetaminophen: a randomized, active and placebo controlled dental pain study.

OBJECTIVES: To address the need for faster pain relief of over-the-counter (OTC) analgesic users, a novel drug delivery technology was developed to achieve faster absorption of orally administered acetaminophen with the goal of delivering earlier onset of pain relief. Previous development studies suggested that a 1000 mg dose of this fast-acting acetaminophen (FA-acetaminophen) formulation provided faster absorption and onset of action versus, commercially available OTC fast-acting analgesics, 1000 mg of extra-strength acetaminophen (ES-acetaminophen) or 400 mg of liquid-filled ibuprofen capsules (LG-ibuprofen). This study was designed as the definitive trial evaluating the onset of pain relief of FA-acetaminophen versus these same OTC comparators. METHODS: This single-dose, randomized, double-blind, placebo- and active-controlled clinical trial compared analgesic onset, overall efficacy, and safety of FA-acetaminophen 1000 mg, ES-acetaminophen 1000 mg, LG-ibuprofen 400 mg, and placebo over 4 h in a postsurgical dental pain model. Following removal of 3 to 4 impacted third molars, 664 subjects with moderate-to-severe pain were randomized in a 4:4:2:1 ratio to FA-acetaminophen (249), ES-acetaminophen (232), LG-ibuprofen (124), or placebo (59). Mean age was 18.9 years; 45.5% were male; 57.5% had severe baseline pain intensity. Subjects stopped a first stopwatch if/when they had perceptible pain relief and a second stopwatch if/when their pain relief became meaningful to them. Pain intensity difference (PID) and pain relief (PAR) were obtained using an 11-point numerical rating scale. FINDINGS: FA-acetaminophen 1000 mg had faster median time to onset of pain relief (15.7 min) compared to ES-acetaminophen 1000 mg (20.2 min, p = 0.035), LG-ibuprofen 400 mg (23.2 min, p < 0.001), and placebo (non-estimable), statistically greater mean PAR and PID scores than other treatment groups at 15 and 30 min, and a statistically greater percentage of subjects with confirmed perceptible pain relief at 15 and 20 min. At 25 min, FA-acetaminophen 1000 mg had a statistically significantly greater percentage of subjects with confirmed perceptible pain relief than LG-ibuprofen 400 mg and placebo. No clinically significant adverse events were reported. CONCLUSIONS: This study supports previous studies, demonstrating faster onset of analgesia with FA-acetaminophen 1000 mg compared to OTC ES-acetaminophen 1000 mg and OTC LG-ibuprofen 400 mg. CLINICALTRIALS.GOV IDENTIFIER: NCT03224403 https://clinicaltrials.gov/ct2/show/NCT03224403.

Analgesic onset and efficacy of a fast-acting formulation of acetaminophen in a postoperative dental impaction pain model.

OBJECTIVES: Speed of onset can be critical to an analgesic's efficacy treating acute pain. To enhance onset, a new oral acetaminophen formulation intended to be fast acting was developed. Two studies evaluated the analgesic onset, efficacy, and safety of this fast-acting acetaminophen (FA-acetaminophen) tablet relative to commercial acetaminophen caplets (ES-acetaminophen) and commercial ibuprofen liquid-filled gelatin capsules (LG-ibuprofen). METHODS: Two single-center, single-dose, inpatient, randomized, double-blind, triple-dummy, placebo-controlled, parallel group design clinical trials were conducted using the postoperative dental impaction pain model. Subjects were healthy men and women aged 17-50 years experiencing moderate-to-severe pain after surgical extraction of at least three impacted third molars. In both studies, four treatment groups were evaluated: 1,000 mg acetaminophen as two 500 mg FA-acetaminophen tablets, 1,000 mg as two 500 mg ES-acetaminophen caplets, 400 mg ibuprofen as two 200 mg LG-ibuprofen capsules, and placebo. To maintain blinding, each subject received six units of study medication. Times to confirmed perceptible pain relief (TCPR) and meaningful pain relief (TMPR) were obtained using the double-stopwatch method. Pain intensity and relief were measured over 6 h following drug administration using a 0-10 numerical rating scale. Time to use of rescue medication (naproxen sodium) and subject global evaluations of study medications at 6 h were collected. Pharmacokinetic blood sampling and safety assessments were performed. RESULTS: Studies 1 and 2 enrolled 240 and 420 subjects, respectively. No clinically important differences among treatment groups were observed for any demographic or baseline characteristics. Efficacy results showed all active treatments statistically superior to placebo. In Study 1, TCPR was statistically significantly shorter for FA-acetaminophen compared to ES-acetaminophen and LG-ibuprofen. In Study 2, no statistically significant differences in TCPR were noted across the active treatment groups. In Study 1, FA-acetaminophen 1,000 mg provided significantly shorter TMPR compared with LG-ibuprofen but not compared with ES-acetaminophen. In Study 2, no significant differences in TMPR were noted across the active treatment groups. In both Study 1 and 2 at 15 min after administration of study drug, PID and PAR scores were greater for FA-acetaminophen than LG-ibuprofen. CONCLUSIONS: Both studies suggested FA-acetaminophen had faster onset of action compared to ES-acetaminophen and LG-Ibuprofen. In light of the difference in TCPR and TMPR results between Study 1 and 2, an additional study is needed to further investigate time to analgesic onset of FA-acetaminophen compared with ES-acetaminophen and LG-Ibuprofen. STUDY REGISTRY NUMBERS: Study 1: NCT02735122; Study 2: NCT03224403.

Analgesic efficacy of naproxen sodium versus hydrocodone/acetaminophen in acute postsurgical dental pain: a randomized, double-blind, placebo-controlled trial.

OBJECTIVES: Opioid/acetaminophen combinations may be overly prescribed in many post-surgical situations where a non-steroidal anti-inflammatory drug with equal or greater efficacy, fewer central nervous system side effects, and no risk for opioid abuse could be substituted. We compared a single, non-prescription dose of naproxen sodium 440 mg (NapS) against hydrocodone plus acetaminophen 10/650 mg (HYD+APAP) in post-impaction surgery pain. METHODS: Single-center, randomized, double-blind, placebo-controlled study in moderate-severe pain after surgical removal of impacted third molars (ClinicalTrials.gov: NCT04307940). Patients (n = 212) received NapS, HYD+APAP, or placebo and were assessed over 12 hours. Primary endpoint: summed pain intensity difference from 0 to 12 hours (SPID0-12). Secondary endpoints: pain intensity, pain relief, time to rescue medication, duration of pain at least half gone. Others: onset of pain relief, global assessment of treatment, adverse events. RESULTS: All 221 randomized patients formed the safety population and were included in the intention-to-treat sensitivity analysis. Nine patients discontinued treatment or had protocol violations, and 212 patients were included in the per-protocol, primary efficacy population. Both active treatments were significantly more effective than placebo. NapS was significantly more effective than HYD+APAP regarding SPID0-12 (p = 0.01; primary endpoint), total pain relief (0-6 and 0-12 hours; p < 0.05), time to rescue medication (p < 0.001), and duration of pain at least half gone (p < 0.001). HYD+APAP was not statistically superior to NapS for any endpoint. More adverse events were reported with HYD+APAP (n = 63) than NapS (n = 2) and placebo (n = 20), including nausea, vomiting, and dizziness. CONCLUSION: In moderate-to-severe postsurgical dental pain, a single dose of NapS was at least as effective as HYD+APAP in the early hours, significantly more effective at reducing pain intensity and providing greater pain relief over 12 hours, and was better tolerated. When not contraindicated, NapS should be considered a preferred alternative to opioid combinations for acute pain. (ClinicalTrials.gov, Identifier: NCT04307940; https://clinicaltrials.gov/ct2/show/NCT04307940).

Longer analgesic effect with naproxen sodium than ibuprofen in post-surgical dental pain: a randomized, double-blind, placebo-controlled, single-dose trial.

Background: Non-steroidal anti-inflammatory drugs (NSAIDs) are recommended as first-line medications in mild-to-moderate acute pain. However, comparative data regarding the duration of analgesia for commonly-used NSAIDs at non-prescription doses is lacking. This study evaluated the time to rescue medication following a single dose of naproxen sodium (NAPSO) vs ibuprofen (IBU) and placebo in subjects with moderate-to-severe post-surgical dental pain.Methods: This single-center, randomized, double-blind, parallel group, placebo-controlled study included healthy subjects with moderate-to-severe baseline pain (Categorical Pain Intensity Scale) who also rated their pain ≥ 5 on a 0-10 pain intensity Numerical Rating Scale following extraction of two impacted mandibular third molars. A single oral dose of NAPSO (440 mg), IBU (400 mg), or placebo was administered. The primary efficacy endpoint was the time to first rescue medication, while secondary endpoints included the sum of pain intensity difference (SPID) and total pain relief (TOTPAR) over 24 h. ClinicalTrials.gov trial registration number: NCT03404206 (EudraCT 2017-005049-67).Results: In the per protocol population (n = 385; mean age = 19 years), the time to rescue medication was significantly (p < .001) longer with NAPSO than IBU and placebo. After treatment, the greatest separation of NAPSO from IBU occurred at 9-14 h and from placebo at 1-6 h. Fewer NAPSO subjects required rescue medication (58/166, 34.9%) compared with IBU (137/165, 83.0%) and placebo (44/54, 81.5%). SPID 0-24 h and TOTPAR 0-24 h were both greater with NAPSO than IBU or placebo.Conclusions: The duration of pain relief after a single dose of NAPSO was significantly longer than after IBU, and significantly fewer NAPSO-treated subjects required rescue medication over a 24-h period.

A Proof-of-concept Study Using Quantitative Sensory Threshold Analysis to Compare Two Intraoral Topical Anesthetics.

PURPOSE: CTY-5339A is an investigational topical anesthetic spray containing 14% benzocaine/2% tetracaine in a metered canister. Each spray delivers ∼0.2 mL of solution. This double-blind, randomized, crossover study compared the local anesthetic effect of CTY-5339A versus 14% benzocaine alone by using 2 quantitative sensory threshold experimental pain paradigms on the maxillary gingiva: pin prick test pain intensity (PPT PI) and heat pain threshold (HPT). METHODS: American Society of Anesthesiology Class 1 and 2 subjects (N = 50) were enrolled in this study. To qualify for the study, subjects were tested on the anterior maxillary gingiva with both PPT and HPT. Subjects had to report a PPT PI of ≥3 on a 0 to 10 numeric pain intensity scale on 1 of 2 consecutive pin pricks separated by 10 s, with at least one score ≥4. After PPT, mean HPT following 2 ramps in the same location had to be ≤ 46.5 °C, with each ramp beginning at 35 °C and an automatic cutoff of 50.6 °C. For treatment visits, subjects were randomly administered either 1 spray of CTY-5339A or 14% benzocaine to the anterior maxillary gingiva within 3 weeks of screening and then the alternative treatment 5 days to 2 weeks later. PPT PI and HPT were recorded immediately before drug application. After drug administration, PPT PI was recorded every minute through 5 min. Commencing at 5 min, PPT PI and HPT were recorded every 5 min through 60 min. For assessment of methemoglobin concentrations, venous blood (5 mL) was drawn from the antecubital fossa both before and 60 min after drug application. Oxygen saturation was recorded via pulse oximetry at baseline and every 10 min. FINDINGS: The AUCs for pain intensity difference from 0-30 and 0-60 min after PPT and HPT differences were significantly greater (P < 0.0001) for CTY-5339A compared with 14% benzocaine. Multiple time points on the time-action curves for PPT PI difference and HPT difference statistically (P < 0.05) favored CTY-5399A. Methemoglobin and oxygen saturation levels did not change compared with baseline after dosing with either treatment. IMPLICATIONS: Recommended doses of CTY-5339A provided significantly more profound and sustained local anesthesia than 14% benzocaine when applied to the maxillary gingiva. Significant changes in methemoglobin or oxygen saturation concentrations did not occur for either drug. ClinicalTrials.gov identifier: NCT03233737.

A Randomized Double-Blind Controlled Trial of Intravenous Meloxicam in the Treatment of Pain Following Dental Impaction Surgery.

This randomized, controlled phase 2 study was conducted to evaluate the analgesic efficacy, safety, and tolerability of single intravenous (IV) doses of 15 mg, 30 mg, and 60 mg meloxicam compared with oral ibuprofen 400 mg and placebo after dental impaction surgery. The primary efficacy end point was the sum of time-weighted pain intensity differences for 0-24 hours postdose. Among 230 evaluable subjects, meloxicam IV 60 mg produced the greatest reduction in pain, followed by the 30-mg and 15-mg doses. Statistically significant differences in summed pain intensity differences over 24 hours were demonstrated for each active-treatment group vs placebo (favoring active treatment) and for meloxicam IV 30 mg and 60 mg vs ibuprofen 400 mg (favoring meloxicam IV). Moreover, there was a statistically significant dose response for meloxicam IV 15 mg to 60 mg. The onset of action for meloxicam IV was rapid and sustained; significant differences in pain intensity differences were detected as early as 10 minutes postdose and lasted through the 24-hour postdose period. Subjects in the meloxicam IV groups were more likely than placebo recipients to achieve perceptible and meaningful pain relief and were less likely to use rescue medication. Patient-reported global evaluation showed that meloxicam IV 60 mg had the highest rating. There were no deaths, serious adverse events, or discontinuations due to adverse events. The incidence of subjects with ≥1 treatment-emergent adverse event was greatest in the placebo group, followed by the groups that received ibuprofen, meloxicam IV 15 mg, 30 mg, and 60 mg. Nausea was the most commonly reported treatment-emergent adverse event. CLINICAL TRIAL REGISTRATION NUMBER: NCT00945763.

Lack of Methemoglobin Elevations After Topical Applications of Benzocaine Alone or Benzocaine Plus Tetracaine to the Oral Mucosa.

PURPOSE: This study evaluated changes in methemoglobin and oxygen saturation concentrations after the administration of recommended doses of 14% benzocaine alone or 14% benzocaine combined with 2% tetracaine. METHODS: American Society of Anesthesiology class 1 and 2 subjects (n = 40) were enrolled in this modified crossover study. Subjects were administered 0.2 mL of 14% benzocaine alone, 0.2 mL of 14% benzocaine plus 2% tetracaine, or 0.4 mL of 14% benzocaine plus 0.2% benzocaine to their cheek mucosa. Venous blood (5 mL) was drawn from the antecubital fossa before and 60 minutes after drug application for methemoglobin analyses. Oxygen saturation was also recorded via pulse oximetry at baseline and every 10 minutes through 60 minutes after drug application. FINDINGS: Methemoglobin and oxygen saturation levels did not change from baseline after the administration of benzocaine alone or when combined with tetracaine. IMPLICATIONS: Recommended doses of benzocaine or benzocaine combined with tetracaine when applied to the cheek mucosa do not induce even clinically insignificant elevations in methemoglobin levels. Metered dosing, such as that used in this study, can help avoid this overdose phenomena with these drugs. ClinicalTrials.gov identifier: NCT02908620.

Pain intensity rating training: results from an exploratory study of the ACTTION PROTECCT system.

Clinical trial participants often require additional instruction to prevent idiosyncratic interpretations regarding completion of patient-reported outcomes. The Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION) public-private partnership developed a training system with specific, standardized guidance regarding daily average pain intensity ratings. A 3-week exploratory study among participants with low-back pain, osteoarthritis of the knee or hip, and painful diabetic peripheral neuropathy was conducted, randomly assigning participants to 1 of 3 groups: training with human pain assessment (T+); training with automated pain assessment (T); or no training with automated pain assessment (C). Although most measures of validity and reliability did not reveal significant differences between groups, some benefit was observed in discriminant validity, amount of missing data, and ranking order of least, worst, and average pain intensity ratings for participants in Group T+ compared with the other groups. Prediction of greater reliability in average pain intensity ratings in Group T+ compared with the other groups was not supported, which might indicate that training produces ratings that reflect the reality of temporal pain fluctuations. Results of this novel study suggest the need to test the training system in a prospective analgesic treatment trial.

Research design considerations for single-dose analgesic clinical trials in acute pain: IMMPACT recommendations.

This article summarizes the results of a meeting convened by the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT) on key considerations and best practices governing the design of acute pain clinical trials. We discuss the role of early phase clinical trials, including pharmacokinetic-pharmacodynamic (PK-PD) trials, and the value of including both placebo and active standards of comparison in acute pain trials. This article focuses on single-dose and short-duration trials with emphasis on the perioperative and study design factors that influence assay sensitivity. Recommendations are presented on assessment measures, study designs, and operational factors. Although most of the methodological advances have come from studies of postoperative pain after dental impaction, bunionectomy, and other surgeries, the design considerations discussed are applicable to many other acute pain studies conducted in different settings.

Efficacy and speed of onset of pain relief of fast-dissolving paracetamol on postsurgical dental pain: two randomized, single-dose, double-blind, placebo-controlled clinical studies.

BACKGROUND: Paracetamol (APAP), also known as acetaminophen, is the most commonly used over-the-counter analgesic for the treatment of mild-to-moderate pain. However, the speed of onset of pain relief is limited mainly to the standard, immediate-release formulation. Efficacy and speed of onset of pain relief are critical in acute pain situations such as postsurgical dental pain, because reducing pain can improve clinical outcome and reduce the risk of transition from acute pain to more chronic pain. Efficacy and rapid onset also reduce the risk of excessive dosing with the analgesic. OBJECTIVE: We sought to investigate the dose-response efficacy and speed of onset of pain relief of a fast-dissolving APAP formulation compared with lower doses of APAP and placebo in dental patients after impacted third molar extraction. METHODS: Two single-center, single-dose, randomized, placebo-controlled, double-blind, double-dummy, parallel-group studies (Study I and Study II) were conducted to evaluate the efficacy and speed of onset of pain relief of different doses of a fast-dissolving APAP tablet (FD-APAP), standard APAP, and placebo in patients with postsurgical dental pain following third molar extraction. In Study I, a single dose of FD-APAP 1000 mg, FD-APAP 500 mg, or placebo was given to 300 patients; in Study II, a single dose of FD-APAP 1000 mg, standard APAP 650 mg, or placebo was given to 401 patients. All 701 patients from both studies were included in the analysis and safety assessment. RESULTS: FD-APAP 1000 mg demonstrated significantly greater effect compared with FD-APAP 500 mg, APAP 650 mg, and placebo for all efficacy measurements, including sum of pain relief and pain intensity difference, total pain relief, sum of pain intensity difference, pain intensity difference, and pain relief score during 6 hours after the dose. Onset of confirmed first perceptible relief in subjects treated with FD-APAP 1000 mg was 15 minutes, which was 32% and 25% significantly shorter than onset of pain relief of FD-APAP 500 mg (22 minutes) and standard APAP 650 mg (20 minutes), respectively. FD-APAP 500 mg and APAP 650 mg demonstrated efficacy over placebo for most of the measurements; however, their effects were significantly lower and lasted for a shorter period of time than for FD-APAP 1000 mg. All study treatments were well tolerated. CONCLUSIONS: FD-APAP 1000 mg tablets demonstrated efficacy over placebo. Also, FD-APAP 1000 mg had significantly superior effect, faster onset, and longer duration of pain relief compared with FD-APAP 500 mg and APAP 650 mg tablets.

A randomized, double-blind, placebo-controlled study of acetaminophen 1000 mg versus acetaminophen 650 mg for the treatment of postsurgical dental pain.

BACKGROUND: Although acetaminophen is one of the oldest and most widely used of all analgesic drugs, the incremental benefit of the 1000-mg dose compared with the 650-mg dose has been questioned. OBJECTIVE: The aim of this study was to assess the relative efficacy of acetaminophen 1000 mg versus acetaminophen 650 mg over a 6-hour period in patients experiencing at least moderate postsurgical dental pain. METHODS: This single-center, randomized, double-blind, placebo-controlled, single-dose study enrolled patients aged 16 to 50 years who experienced at least moderate pain after surgical removal of impacted third molars. Each patient received either acetaminophen 1000 mg (n = 239), acetaminophen 650 mg (n = 241), or placebo (n = 60) when they had at least moderate pain and a score ≥50 on the 100-mm Visual Analog Scale (VAS) postsurgically. Pain intensity and pain relief were measured over 6 hours (VAS 0-100 mm). RESULTS: All 540 patients (52% female; age range, 16-30 years; 95% white) were included in the efficacy analysis. For the primary efficacy endpoint (weighted sum of the pain intensity difference from baseline [PID] and pain relief [PAR] scores over 6 hours [SPRID6]), acetaminophen 1000 mg demonstrated a 24% improvement compared with acetaminophen 650 mg (529.4 vs 427.3; P = 0.001). In addition, acetaminophen 650 mg was significantly superior compared with placebo (P < 0.001). The weighted sum of PID over 6 hours (SPID6), the weighted total pain relief over 6 hours (TOTPAR6), and the percentage of patients with >50% of the maximum possible TOTPAR6 score were significantly greater for patients treated with acetaminophen 1000 mg compared with those receiving acetaminophen 650 mg (P ≤ 0.006) or placebo (P < 0.001) and for patients treated with acetaminophen 650 mg compared with placebo (P < 0.001). Time to rescue, rescue rates through 4 and 6 hours, and patient global assessment demonstrated similar findings. Patients treated with acetaminophen 1000 mg or 650 mg had a significantly different distribution in times to confirmed perceptible and meaningful pain relief compared with those receiving placebo (P < 0.001). Adverse events were reported by 18.5% of patients, with no clinically important difference between active treatment groups and placebo. CONCLUSIONS: Acetaminophen 1000 mg provided clinically meaningful and statistically significantly greater efficacy in treating postsurgical dental pain compared with acetaminophen 650 mg and placebo. The outcomes of this study are limited to the single-dose design of this study. ClinicalTrials.gov identifier: NCT01115673.

The value of the dental impaction pain model in drug development.

The modern version of the Dental Impaction Pain Model (DIPM) was developed in the mid-1970s. Since that time, several hundred studies have been conducted by numerous investigators. Today it is arguably the most utilized of all the acute pain models. Its popularity is due to the success rate of the studies, fast subject entry, and cost effectiveness. The surgical procedure is extremely standardized, and the surgery requires either minimal or no use of CNS depressant anesthetics. The methodology is similar to that utilized in other acute pain models; however, the DIPM is much more versatile than most other models. The model can be easily adapted to perform multiple-dose studies, pharmacokinetics/pharmacodynamics (PK/PD) correlations, preemptive interventions, and sleep-pain studies. A few investigators have even developed microdialysis techniques, wherein they insert probes into extraction sockets to collect exudates for measuring biochemical mediators of pain or drug levels at the site of injury. In many instances, an accomplished site can complete a study of several hundred subjects in approximately 3 months. There are studies in the literature that have incorporated up to six treatment arms in one study and clearly separated the drugs from each other. The exquisite assay sensitivity is due to the homogeneity of the study population, the predictable level and appropriate intensity of the postsurgical pain, and the minimizing of variability by using only one or two study centers. The DIPM has been employed to evaluate NSAIDs (both nonselective and selective Cox inhibitors), opioids and combination analgesics, as well as some investigational drugs with unique mechanisms of action. The model is particularly useful for proof-of-concept studies that require dose-ranging and profiling the time-effect curve for efficacy including onset, peak effect, and duration of analgesic activity.

Double-blind, randomized, parallel, placebo-controlled study of ibuprofen effects on thromboxane B2 concentrations in aspirin-treated healthy adult volunteers.

BACKGROUND: Patients taking aspirin for cardioprotection may occasionally take over-the-counter (OTC) ibuprofen for pain relief, which might interfere with the antiplatelet effects of aspirin. OBJECTIVE: The present study was undertaken to determine whether ibuprofen, taken according to OTC label directions, would affect inhibition of thromboxane B2 (TXB2), a surrogate for platelet inhibition. METHODS: This was a prospective, multiple-dose,single-center, double-blind, randomized, parallel, placebo-controlled study. Eligible subjects received chewable, immediate-release aspirin 81 mg QD for 8 days, and were then randomized to receive either ibuprofen 400 mg TID or placebo TID, in addition to aspirin, for 10 days. RESULTS: Fifty-one subjects were randomized; 47(24 placebo, 23 ibuprofen) completed the study. No subjects withdrew prematurely. Subjects were predominantly white (49%) or black (38%), and 53% were male. The mean (SD) age was 38.4 (9.8) years and mean (SD) body weight was 173.2 (26.7) pounds. On days 1, 3, 7, and 10 of the study period, mean TXB2 inhibitions were 99.24%, 98.88%, 97.75%, and 98.17% for ibuprofen and 98.82%, 98.93%, 98.75%, and 98.83% for placebo. Although a statistically significant reduction of TXBZ inhibition was seen in the ibuprofen group at days 7 and 10 (P = 0.003 and P = 0.023, respectively), TXBZ inhibition was >90% on all days tested in all subjects. Aspirin, ibuprofen, and placebo were all well tolerated. There were 3 adverse events (1 mild and 2 moderate) during the aspirin run-in period and 8 (2 mild and 6 moderate) during the randomized study period. CONCLUSIONS: No clinically meaningful loss of cardioprotection was found, as reflected by TXB2 inhibition in healthy volunteers who received OTC doses of ibuprofen. When using this regimen of OTC ibuprofen with immediate-release, low-dose aspirin, concerns about the loss of cardioprotective antiplatelet effects of aspirin are not supported by this study.

Addition of ibuprofen to pseudoephedrine and chlorpheniramine in the treatment of seasonal allergic rhinitis.

BACKGROUND: Patients with seasonal allergic rhinitis experience many nasal and concomitant nonnasal symptoms. Many patients also experience headaches and facial pain, pressure, or discomfort. Standard over-the-counter therapy with antihistamines and nasal decongestants often does not completely relieve all symptoms associated with allergic rhinitis. OBJECTIVE: To establish the contribution of ibuprofen when used with pseudoephedrine and chlorpheniramine, a standard over-the-counter regimen, to relieve the symptoms of seasonal allergic rhinitis. METHODS: In this 7-day, multicenter, randomized, placebo-controlled, double-blind, double-dummy, parallel-group trial, qualified subjects were randomly assigned to 1 of 4 treatment groups that received combined ibuprofen/pseudoephedrine/chlorpheniramine (200/30/2 mg or 400/60/4 mg), combined pseudoephedrine/chlorpheniramine (30/2 mg), or placebo. Therapy began when the subject experienced a minimum of moderate allergy-associated pain, and it continued 3 times a day for 7 consecutive days. RESULTS: Mean pain intensity reduction in both ibuprofen/pseudoephedrine/chlorpheniramine treatment groups was 40% greater than in the placebo group and 33% greater than in the pseudoephedrine/chlorpheniramine treatment group (P < .001). Mean changes from baseline in total and nonpain symptom scores for both ibuprofen/pseudoephedrine/chlorpheniramine doses were significantly greater than for placebo (P < .001) and pseudoephedrine/chlorpheniramine (P < .001-.05) but were not different from each other. Ibuprofen enhanced the chlorpheniramine and pseudoephedrine effects, resulting in incremental 33% to 34% pain relief and 17% to 22% allergy symptom relief compared with pseudoephedrine/chlorpheniramine. CONCLUSIONS: In both doses of the triple combination, ibuprofen added to the effects of chlorpheniramine and pseudoephedrine, resulting in superior relief of pain and all nonpain allergy symptoms compared with pseudoephedrine/chlorpheniramine treatment. Furthermore, the superior efficacy of the lower dose of the triple combination allowed for a decrease in the incidence of adverse effects.

Efficacy and tolerability of nonprescription ibuprofen versus celecoxib for dental pain.

Many clinicians appear confused about the purported clinical advantages of the new generation COX-2 inhibitors compared to both over-the-counter and prescription nonsteroidal anti-inflammatory analgesic agents (NSAIDs). Infact, there is a paucity of published information comparing the safety and efficacy of these two classes of drugs when used to treat acute pain. This study was designed to compare the safety and analgesic efficacy of an over-the-counter (OTC) analgesic, ibuprofen (Advil Liqui-Gels), to the leading prescription COX-2 inhibitor celecoxib (Celebrex). Ibuprofen liquigel is an encapsulated, solubilized potassium salt of ibuprofen that has a higher Cmax and shorter tmax than traditional ibuprofen solid-dosage formulations. This trial evaluated the maximum approved OTC dosing regimen (400 mg x 3, q4-6h) of ibuprofen liquigels compared to a single dose of celecoxib (200 mg) and placebo in 174 patients with moderate orsevere pain following surgical extraction of impacted third molars. The study design was multiple dose, randomized (stratified by baseline pain and gender), placebo controlled, double blind, double dummy, and parallel group. The onset of pain relief was determined using a two-stopwatch procedure. Treatments were also compared using standard indices of pain intensity and pain relief. The study demonstrated assay sensitivity in that both active medications were significantly more effective than placebo for all efficacy measures. In comparing the two active medications, the time to meaningful relief was significantly shorter, and the mean 4-, 8-, and 12-hour summed pain relief combined with pain intensity difference scores were significantly higher for ibuprofen liquigels compared with celecoxib (p < 0.001). Analyses of other key efficacy variables, including the time to rescue medication and the patients' overall assessment of study medication, confirmed the superior efficacy of ibuprofen liquigels over celecoxib. Both active treatments were well tolerated, with no differences in incidence or severity of adverse events. Of particular interest, there were no differences in gastrointestinal-related side effects when comparing these doses of ibuprofen liquigels to celecoxib. In conclusion, ibuprofen liquigels were a significantly more effective analgesic and provided relief significantly faster compared with celecoxib in the treatment of postsurgical pain.

The Analgesic Interaction of Misoprostol with Nonsteroidal Anti-Inflammatory Drugs.

The purpose of this project was to evaluate the analgesic efficacy of misoprostol when combined with ibuprofen or diclofenac Na. Animal experiments using the inflamed rat paw formalin model suggested that misoprostol potentiates the analgesic effect of some NSAIDs (nonsteroidal anti-inflammatory drugs) including diclofenac Na but not propionic acid derivatives or opiates. The dental pain model was used to evaluate the clinical relevance of this interaction. Patients received a single oral dose of study medication following surgical removal of impacted teeth. Patients were medicated for moderate to severe postsurgical pain and then filled in an analgesic diary for a 6-h observation period. Several blood samples were taken over the observation period. In addition, microdialysis samples were taken directly from the extraction socket and were analyzed for immunoreactive prostaglandin E(2) levels. The studies were single-dose, parallel group and double-blind assays. In the first study, 70 patients received an oral dose of either placebo (n = 13), misoprostol 200 &mgr;g (n = 18), ibuprofen 200 mg (n = 19), or the combination of misoprostol + ibuprofen (n = 20). Misoprostol alone demonstrated a small analgesic effect compared to placebo. Both the ibuprofen and combination groups were substantially more effective than placebo but not different from each other. The combination group had higher ibuprofen blood levels during the first 45 min but had a lower C(max) and longer time to T(max). The second study evaluated oral doses of placebo (n = 11), misoprostol 200 &mgr;g (n = 21), diclofenac Na 50 mg (n = 18), and the combination of misoprostol + diclofenac Na (n = 20). Relative to placebo, misoprostol performance was similar to the first study. When the results of the two studies were combined, there was a small, but statistically significant, analgesic effect for misoprostol. Diclofenac Na was superior to both placebo and to misoprostol alone. The combination was the most effective treatment, and for hours 4--6 it was significantly better than diclofenac Na alone. Analysis of the blood samples showed an earlier and higher peak effect for the diclofenac Na group compared to the combination, and the combination again had a lower C(max). The microdialysis probe assays demonstrated that misoprostol depressed PGE(2) levels at the peripheral site of trauma over the first 2 h after surgery. These pilot studies used small samples, and the results only suggest trend effects. Both studies demonstrated that misoprostol 200 &mgr;g, a prostaglandin analog, does have an analgesic effect. When combined with ibuprofen, there was no potentiation of analgesia. In contrast, the combination of misoprostol + diclofenac Na demonstrated an enhanced peak effect, total effect for pain intensity difference and pain relief (sum pain intensity difference [SPID] and total pain relief [TOTPAR]), and