carisoprodol / Generic mfg. - LARVOL DELTA

Carisoprodol poisoning with serotonin toxicity. (PubMed, BMJ Case Rep) - "Here, we present a case of serotonin syndrome with carisoprodol holding a pivotal role. This case highlights the potential serotonergic activity of carisoprodol which contradicts the agent's supposed GABAergic mechanism of action."

Journal

First enantioseparation and stereoselective metabolism of carisoprodol in rat liver microsomes. (PubMed, J Pharm Biomed Anal) - "The results revealed that hepatic microsomes metabolize one enantiomer at a significantly faster rate than the other. The work provides valuable insights into the underexplored metabolism of carisoprodol, laying the ground for future pharmacological studies on the single enantiomers."

Journal • Preclinical

Recommendations for Toxicological Investigation of Drug-Impaired Driving and Motor Vehicle Fatalities-2025 Update. (PubMed, J Anal Toxicol) - "Tier I and Tier II screening and confirmation scope and cutoffs were re-evaluated to update the recommendations. Carisoprodol and meprobamate were moved to the Tier II scope from Tier I; gabapentin was promoted to the Tier I scope from Tier II; screening cutoffs were differentiated for immunoassay versus non-immunoassay (e.g. chromatographic) screening for blood and oral fluid; cross-reactivity screening requirements were removed and clarified with specific cutoff values; several cutoffs for screening and confirmation were increased or removed for blood and oral fluid; urine was removed as a recommended matrix for testing in cases involving suspected drug impairment."

Journal

Non-targeted metabolite characterization in microsomal assay using liquid chromatography coupled to high-resolution mass spectrometry: Application to carisoprodol. (PubMed, J Pharm Biomed Anal) - "This study highlights the effectiveness of a multi-technique analytical approach for elucidating drug metabolism. The integration of LC-HRMS, isotopic labelling, and computational tools provides a comprehensive platform for metabolic characterization, while emphasizing the necessity of experimental validation in refining in silico predictions."

Journal

Urinary metabolic ratio of pain management and substance abuse treatment drugs: Drug-drug interactions. (PubMed, J Opioid Manag) - "The 18 drugs include dextromethorphan, oxycodone, hydrocodone, tramadol, morphine, buprenorphine, fentanyl, clonazepam, alprazolam, quetiapine, carisoprodol, tapentadol, ketamine, methadone, impramine, and amitriptyline. The 14 interfering drugs include fluoxetine, paroxetine, bupropion, citalopram, sertraline, venlafaxine, duloxetine, risperidone, trazodone, aripiprazole, cyclobenzaprine, amphetamine, and tetrahydrocannabinol...Using the MR reference intervals of the 18 drug pairs established in an earlier study, and the current DDI system, we can alert providers of unusual metabolism caused by DDIs. This will help providers do better prescribing or review more closely all medications and supplements patients are taking, thus avoiding underdosing or potential medication adverse reactions."

Journal • Pain • Substance Abuse • CYP2C19 • CYP3A4

Urinary metabolic ratio of pain management and substance abuse treatment drugs: Reference intervals. (PubMed, J Opioid Manag) - "These drugs were dextromethorphan, morphine, oxycodone, hydrocodone, quetiapine, tapentadol, tramadol, buprenorphine, clonazepam, fentanyl, imipramine, ketamine, carisoprodol, alprazolam, methadone, and amitriptyline. Ratio values outside of this reference range could be considered to be caused by genetic metabolizing variants, drug-drug interactions, age, or deception. Alerting providers of the variance in metabolism from the expected norm might reduce overdosing or underdosing patients."

Journal • Pain • Substance Abuse

Drug-induced cardiac arrest: a pharmacovigilance study from 2004-2024 based on FAERS database. (PubMed, Front Cardiovasc Med) - "The top five drugs identified by ROR were: carisoprodol [ROR (95% CI): 34.13 (29.62-39.32)], sugammadex [ROR (95% CI): 26.93 (22.56-32.16)], regadenoson [ROR (95% CI): 20.00 (17.69-22.60)], alprazolam [ROR (95% CI): 12.82 (12.19-13.48)], and propofol [ROR (95% CI): 11.93 (10.61-13.41)]. This study identifies over 40 drugs potentially associated with an elevated risk of CA based on FAERS data. Healthcare professionals should be particularly vigilant when prescribing these drugs, especially to patients with a history of heart disease, and ensure rigorous monitoring of their cardiac health."

Adverse events • Journal • Cardiovascular • Heart Failure • Musculoskeletal Diseases • Oncology

LIDOCAINE INFUSION FOR TREATMENT OF CHRONIC INTRACTABLE POST-TRAUMATIC HEADACHE (ASRA-SPRING 2025) - "• Trialed over 60 medications including opioids, muscle relaxants, SSRIs, and carisoprodol 350 mg, with only mild relief • Tried lifestyle modifications and occipital nerve blocks in the past with only mild relief • Patient presented to pain clinic with chronic intractable headaches and debilitating nausea 2-3x/month Patient received monthly lidocaine IV infusions, bilateral neck trigger point injections, and right great occipital nerve blocks with significant improvement in pain...• The mixture optimized after several visits to include the following drugs in 1000 ml LR: ketamine (.5-1mg/kg), lidocaine (1-2mg/kg), midazolam (0.2-0.5mg/kg), ondansetron (4-8mg), dexamethasone (4-8mg) • After careful preparation, the 1000 ml solution is infused over 90 minutes through a peripheral IV...CONCLUSIONS Candidates for IV lidocaine infusion therapy exhibit chronic pain secondary to prolonged opioid treatment resulting in long term alteration of opioid receptors. Our treatment aims..."

Anesthesia • Cardiovascular • CNS Disorders • Diabetic Neuropathy • Hypertension • Neuralgia • Pain • Thermal Injury

Intrauterine Exposure to Psychotropic Medications as a Risk Factor for Neonatal Opioid Withdrawal Syndrome (PAS 2025) - "Those with exposure to psychotropic medication were more likely to also have exposure to other substances (i.e., alcohol, nicotine, marijuana, and methamphetamine) (84% vs. 69%; p< 0.05; Table 1). Of the 1,305 infants included in the ESC-NOW study, 297 (22.8%) had antenatal co-exposure to psychotropic medications. The mean length of stay was 1.6 days longer for infants with psychotropic exposure compared to those without exposure (12.1 vs. 10.5 days, respectively; p < 0.001) (Table 2)."

Clinical • Addiction (Opioid and Alcohol) • Substance Abuse

Effects of the Prescription Drug Monitoring Program Mandate on Queries of Controlled Substance Prescriptions: Findings from Texas. (PubMed, J Am Pharm Assoc (2003)) - "The immediate impact of the Texas PDMP may be limited, particularly given that the mandate's implementation coincided with the COVID-19 pandemic. To more effectively address controlled substance misuse, the state should consider strengthening the mandate and exploring additional measures to enhance its impact."

Journal • Infectious Disease • Novel Coronavirus Disease

Low Dose Naltrexone for Treatment of Severe Hemochromatosis Pain (IARS-SOCCA 2025) - "Pharmacologically, he has tried various combinations of multimodal pain regimen—including acetaminophen, oxycodone, gabapentin, pregabalin, cyclobenzaprine, baclofen, tizanidine, carisoprodol, dexamethasone, and amitriptyline—with minimal to no pain relief...His current pain regimen includes LDN at 6 mg twice daily, gabapentin 900 mg three times daily, and duloxetine 60 mg daily... We present a patient with severe pain from hemochromatosis and arachnoiditis that was refractory to numerous interventions and medical treatments. Remarkably, noticeable pain improvement was achieved only with initiation of low-dose naltrexone (LDN). This case is noteworthy as there is no documented use of LDN specifically for hemochromatosis-associated pain and in this case it has been the only effective therapy trialed."

Anesthesia • CNS Disorders • Crohn's disease • Fatigue • Gastroenterology • Genetic Disorders • Hematological Disorders • Hepatology • Immunology • Inflammation • Inflammatory Bowel Disease • Multiple Sclerosis • Orthopedics • Pain • Rheumatology • Urinary Incontinence

Health Ministry Halts Export of Unapproved Drug Combination (Chemical Industry Digest) - "The health ministry has taken strict action against Aveo Pharmaceuticals, Mumbai, following reports of the company exporting unapproved drug combinations containing Tapentadol and Carisoprodol to West African countries. The ministry issued a stop-activity order and revoked the company’s export no-objection certificate (NoC) and manufacturing licenses for these combinations...However, the combination of these two drugs has not received approval in India. The ministry also clarified that neither drug is classified under India’s Narcotic Drugs and Psychotropic Substances (NDPS) list....During the investigation, officials seized all raw materials, in-process substances, and finished products. They confiscated approximately 1.3 crore (13 million) tablets and capsules, along with 26 batches of Active Pharmaceutical Ingredients (APIs) of Tapentadol and Carisoprodol."

Commercial • Pain

The role of prescribed controlled substance acquisition as potential triggers of opioid overdose: A case-crossover study. (PubMed, Int J Drug Policy) - "Controlled substance prescription acquisition, particularly opioids in combination with carisoprodol and/or benzodiazepines, are potential triggers of opioid overdose."

Journal • Addiction (Opioid and Alcohol) • CNS Disorders

Post-rehab Pain Management Using Jain Auricular Acupuncture for Pain (JAAP): A Case Report (ACRM 2024) - "She was given acetaminophen and carisoprodol every 8 hours as needed... This highlights the need for education about the possible benefits and risks of acupuncture and how it can be incorporated into the treatment plan. Along with medical management and therapies, acupuncture can be an adjuvant therapy in the post-acute setting following a hip fracture. This is crucial to consider in cases of patients with multiple medications or those wanting to avoid the addition of medications."

Case report • Clinical • Immunology • Musculoskeletal Diseases • Orthopedics • Pain

BATTLING THE BLOCKADE: A CASE OF MULTIFACTORIAL SHOCK IN POLYSUBSTANCE OVERDOSE (CHEST 2024) - "CASE PRESENTATION: A 59-year-old female with a past medical history of anxiety, hypertension, and hyperlipidemia presented with lethargy following an intentional overdose of carvedilol, amlodipine, carisoprodol, tramadol, alprazolam, and clonidine...Initial management consisted of high-dose insulin with D10 infusion, glucagon, calcium gluconate, magnesium sulfate, n-acetylcysteine, and methylene blue... Polysubstance overdose carries a significant mortality rate with some intoxications resulting in shock and ultimately death. Early recognition of shock etiology can facilitate in choosing appropriate management and possibly reduce mortality. In the setting of CCB and BB overdose, ILE may improve patient outcomes by acting as a reservoir for these lipophilic medications and stabilize cardiac function."

Clinical • Cardiovascular • Dyslipidemia • Hypertension • Mood Disorders • Psychiatry

Adverse effects from counterfeit and mislabeled medicine containing tapentadol and carisoprodol. (PubMed, Clin Case Rep) - "When self-administration with counterfeit or mislabeled medicine is suspected, comprehensive laboratory analysis should be preferred over immunoassay screening to avoid false negative results. Carisoprodol, which was formerly a popular muscle relaxant drug in many countries, has reappeared on illegal drug markets, and may cause an itching, purple-colored rash, even after a single dose."

Adverse events • Journal

Impact of Mandated Use of the Texas Prescription Monitoring Program on Carisoprodol Dispensing in Texas (ISPOR 2024) - "There is no sufficient evidence for the associations between the Texas PMP mandate and changes in carisoprodol prescribing and dispensing. Future research is warranted to continuously monitor the trend in carisoprodol dispensing and explore factors that may hinder the adoption of the PMP mandate by prescribers and dispensers in Texas."

Tizanidine: Advances in Pharmacology & Therapeutics and Drug Formulations. (PubMed, J Pain Res) - "From the perspective of drug safety, tizanidine has lower incidences of adverse events (injury, delirium, encephalopathy, falls, and opioid overdose) compared to baclofen, no association with risk of Alzheimer's disease as with orphenadrine, no risk of serotonin syndrome like metaxalone when comedicated with serotonergic drugs, no significant pharmacokinetic changes in CYP2C19 poor metabolizers unlike diazepam and carisoprodol, and no physically addictive or abuse properties like carisoprodol and diazepam. Tizanidine is an SMR with unique features and may be an optimal initial choice for older adults. There would be more scientific studies, wider therapeutic applications, and new drug formulations in the future."

Journal • Review • Addiction (Opioid and Alcohol) • Alzheimer's Disease • CNS Disorders • Musculoskeletal Diseases • Musculoskeletal Pain • Neuralgia • Oncology • Pain • CYP2C19

Comparative Risk of Injury with Concurrent Use of Opioids and Skeletal Muscle Relaxants. (PubMed, Clin Pharmacol Ther) - "In the oxycodone-SMR-triggered cohort, the adjusted hazard ratios (HRs) were 1.86 (95% CI, 1.23-2.82) for carisoprodol and 1.73 (1.09-2.73) for tizanidine. In the tramadol-synchronically triggered cohort, the adjusted HRs were 0.69 (0.49-0.97) for metaxalone and 0.62 (0.42-0.90) for tizanidine. In the tramadol-SMR-triggered cohort, the adjusted HRs were 1.51 (1.01-2.26) for baclofen and 1.48 (1.03-2.11) for cyclobenzaprine...In conclusion, the relative injury rate associated with different SMRs used concurrently with the three most dispensed opioids appears to vary depending on the specific opioid and the order of combination initiation. If confirmed by future studies, clinicians should consider the varying injury rates when prescribing SMRs to individuals using hydrocodone, oxycodone, and tramadol."

Journal

Carisoprodol-Induced Status Epilepticus in a Young Adult With End-Stage Renal Disease (SCCM 2024) - "She was loaded with levetiracetam and continued scheduled dosing. However, Norwegian and European medical authorities withdrew this medication due to the side effect profile. Medical providers must be aware of carisoprodol in new onset seizure or altered mental status differential."

Clinical • Back Pain • Cardiovascular • Depression • Epilepsy • Hypertension • Musculoskeletal Pain • Nephrology • Pain • Psychiatry • Renal Disease

Opioid and benzodiazepine utilization patterns in metropolitan and rural Texas. (PubMed, J Opioid Manag) - "Rural patients had more benzodiazepine and opioid days overlap than urban patients. The prevalence is higher among older adults and providers who practice in rural areas (average 8.2 more days per quarter). Our findings in Texas indicate a trend downward in overlap for both rural and urban areas over the last year of measurement. However, rural areas are still significantly higher."

Journal • Addiction (Opioid and Alcohol)

Impact of 30-day prescribed opioid dose trajectory on fatal overdose risk: A population-based, statewide cohort study. (PubMed, J Gen Intern Med) - "Large (≥2 categories) 30-day dose increases and decreases were both associated with increased risk of fatal opioid overdose, particularly for patients taking ≥90 MME whose opioids were abruptly stopped. Results align with 2022 CDC guidelines that urge caution when reducing opioid doses for patients taking long-term opioid for chronic pain."

Journal • Addiction (Opioid and Alcohol) • CNS Disorders • Pain

The Role of Prescribed Controlled Substance Acquisition As Potential Triggers of Opioid Overdose: A Case-Crossover Study (ISPOR 2023) - "Binary CS variables indicating presence or absence of: any CS, opioid, benzodiazepine, opioid and benzodiazepine, stimulant, sedative, carisoprodol, and pregabalin were created. Additionally, cumulative morphine milliequivalents were calculated for each time window... The recent acquisition of a CS prescription, specifically opioids, benzodiazepines, and carisoprodol, was associated with increased risk of OOD."

Clinical • Addiction (Opioid and Alcohol) • CNS Disorders

The associations between central serous chorioretinopathy and muscle relaxants: A case-control study. (PubMed, Taiwan J Ophthalmol) - "We found muscle relaxants to be associated factors of CSC regardless of inclusion of corticosteroids/sympathomimetics (P < 0.05). Among individual classes of muscle relaxants in this study, only eperisone/tolperisone posed a significant risk (P < 0.05). The vascular smooth muscle relaxation could be the possible mechanism that affects the choroidal blood flow and indirectly predisposes to CSC."

Journal • Retinal Disorders

Early Drug Prescription Patterns as Predictors of Final Workers Compensation Claim Costs and Closure: An Updated Analysis on an Expanded Cohort. (PubMed, J Occup Environ Med) - "Prescription patterns in the first 3 months or first 6 months of workers' compensation claim development may be used as predictors of claim outcomes."

Journal • CNS Disorders