Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
DISULFIRAM vs ACTIQ
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Disulfiram irreversibly inhibits aldehyde dehydrogenase, causing accumulation of acetaldehyde after alcohol ingestion, leading to aversive effects such as flushing, nausea, and hypotension.
Opioid agonist; binds to mu-opioid receptors in the CNS, altering pain perception and response.
Alcohol dependence (FDA-approved),Off-label: Cocaine dependence (limited evidence)
Management of breakthrough pain in cancer patients aged 16 and older who are already receiving and tolerant to opioid therapy for their underlying persistent cancer pain
250 mg orally once daily, increased to 500 mg orally once daily if needed; maintenance dose typically 250 mg per day (range 125-500 mg).
200 mcg transmucosally, titrated upward as needed; initial dose for opioid-tolerant patients is 200 mcg, with additional doses possible after 15 minutes if needed. Maximum 4 doses per episode. At least 4 hours between episodes.
Approximately 7–10 hours for parent drug; however, the disulfiram-ethanol reaction can persist up to 14 days due to irreversible inhibition of aldehyde dehydrogenase (ALDH) and slow regeneration of the enzyme. The active metabolite, diethyldithiocarbamate, has a half-life of about 15 hours.
Terminal half-life 0.83–2 hours (mean 1.3 h) in adults; note that context: transmucosal absorption leads to rapid onset but short duration; half-life is not correlated with clinical effect due to oral transmucosal route and rapid redistribution.
Disulfiram is rapidly metabolized in the liver to diethyldithiocarbamate, which is further metabolized; it is primarily excreted in urine and feces.
Primarily hepatic via CYP3A4 to inactive metabolites (norfentanyl, despropionylfentanyl, hydroxyfentanyl) and other metabolites; <7% excreted unchanged in urine.
Primarily renal as metabolites; approximately 80% of a dose is excreted in urine as glucuronide conjugates and other metabolites, with less than 20% excreted in feces via bile. A small amount is eliminated unchanged in urine.
Primarily renal as metabolites (about 75% as metabolites, <10% unchanged). Fecal excretion accounts for <9%. Biliary excretion is minor.
Approximately 96% bound primarily to albumin and also to lipoproteins.
Fentanyl is 80–85% bound to plasma proteins (primarily albumin and α1-acid glycoprotein).
Approximately 2–4 L/kg, indicating extensive tissue distribution and accumulation, particularly in adipose tissue due to lipophilicity.
Approximately 4 L/kg (range 3–6 L/kg); large Vd indicates extensive tissue distribution and redistribution contributing to short duration.
Rapidly and almost completely absorbed after oral administration; absolute bioavailability is approximately 70–90% due to first-pass metabolism in the liver. No parenteral forms are approved; only oral route (tablets) is used clinically.
Oral transmucosal: 50% (range 47–54%) relative to IV; variable and enhanced by rapid absorption through buccal mucosa.
No dose adjustment required for renal impairment; no specific GFR-based guidelines exist; use with caution in severe renal impairment.
No specific GFR-based dose adjustment recommended; use with caution in severe renal impairment (Cr Cl < 30 m L/min) and consider dose reduction due to potential accumulation.
Contraindicated in severe hepatic impairment (Child-Pugh class C). In mild to moderate impairment (Child-Pugh A or B), no specific dose adjustment, but monitor liver function. Not recommended in active liver disease.
Child-Pugh Class A/B: No adjustment. Child-Pugh Class C: Reduce initial dose to 100 mcg and titrate slowly; monitor closely for prolonged effects.
Not recommended for use in patients under 18 years due to lack of established safety and efficacy.
Not approved for pediatric use; safety and efficacy not established in patients under 16 years.
Initiate at lower dose (125 mg/day) due to age-related decreased function; monitor closely for adverse effects.
Initiate at 100 mcg transmucosally; titrate slowly due to increased sensitivity and risk of respiratory depression. Monitor for adverse effects.
Disulfiram should never be administered to a patient who is in a state of alcohol intoxication or without the patient's full knowledge and consent. The patient must be fully informed of the disulfiram-alcohol reaction.
Risk of respiratory depression, addiction, abuse, and misuse; accidental ingestion can be fatal; concomitant use with benzodiazepines or CNS depressants may cause profound sedation, respiratory depression, coma, and death; not for use in opioid non-tolerant patients; risk of neonatal opioid withdrawal syndrome with prolonged use during pregnancy; serious, life-threatening, or fatal respiratory depression may occur even at recommended doses.
Hepatotoxicity including hepatitis and hepatic failure; peripheral neuropathy; optic neuritis; psychotic reactions; hypersensitivity; risk of severe disulfiram-alcohol reaction if alcohol is consumed.
Risk of respiratory depression; addiction, abuse, and misuse; interactions with CNS depressants; serotonin syndrome; adrenal insufficiency; severe hypotension; seizures; withdrawal; use in patients with head injuries, increased intracranial pressure, biliary tract disease, pancreatitis; risk of choking with lozenge; oral mucosal irritation; dental caries; hypokalemia; hyponatremia; use in elderly, cachectic, or debilitated patients.
Concurrent use of alcohol or alcohol-containing preparations; metronidazole; paraldehyde; severe myocardial disease; coronary occlusion; psychosis; severe hepatic impairment; hypersensitivity to disulfiram or other thiuram derivatives.
Significant respiratory depression; acute or severe bronchial asthma in an unmonitored setting or without resuscitative equipment; known or suspected paralytic ileus; hypersensitivity to fentanyl or any component; opioid non-tolerant patients; management of acute or postoperative pain including headache/migraine, dental pain, or emergency department use.
Avoid foods and products containing alcohol: sauces (e.g., wine sauces, beer batter), vinegar (especially red/white wine vinegar), marinades, ripe fruits (fermentation can produce trace alcohol), some desserts (e.g., tiramisu, fruitcakes), alcohol-infused chocolates, non-alcoholic beer/wine (may contain up to 0.5% alcohol). Also avoid mouthwashes, breath sprays, and hand sanitizers with ethanol. Some medications like paraldehyde, chloral hydrate, and metronidazole may cross-react. Even alcohol in cooking may not fully evaporate and can trigger a reaction.
No significant food interactions. Grapefruit juice may increase fentanyl levels, but specific studies with ACTIQ are lacking. Avoid alcohol, as it may increase sedation and respiratory depression risk.
Pregnancy Category C. First trimester: Limited human data; animal studies show embryotoxic effects at high doses. Avoid unless benefit outweighs risk. Second and third trimesters: No specific malformation patterns reported; however, theoretical risk of disulfiram-ethanol reaction causing fetal hypoxia due to maternal acetaldehyde accumulation. Use only if essential and with strict alcohol avoidance.
FDA Pregnancy Category C. First trimester: limited human data; animal studies show increased resorptions and fetal growth restriction. Second/third trimester: chronic use may cause neonatal opioid withdrawal syndrome; avoid use during labor due to risk of neonatal respiratory depression.
Excreted into breast milk in small amounts (M/P ratio not established). No adverse effects reported in nursing infants. However, theoretical risk of disulfiram-ethanol reaction if mother consumes alcohol. Recommend caution and discuss with healthcare provider; generally consider compatible with breastfeeding if mother abstains from alcohol.
Excreted in breast milk; M/P ratio not established. Limited data suggest low levels, but risk of infant sedation and respiratory depression. Avoid use while breastfeeding unless potential benefit outweighs risk.
No specific dose adjustment recommended in pregnancy. Pharmacokinetic studies in pregnancy not available. Use lowest effective dose (typically 250 mg/day) to minimize risks. Avoid higher loading doses. Discontinue if signs of hepatotoxicity occur.
Due to increased plasma volume and hepatic metabolism in pregnancy, dose requirements may increase; adjust based on clinical response and tolerance. Avoid use during labor and delivery due to risk of neonatal respiratory depression; short-term use preferred.
Disulfiram irreversibly inhibits aldehyde dehydrogenase, causing accumulation of acetaldehyde after alcohol ingestion, leading to severe nausea, vomiting, hypotension, and flushing. Avoid use in patients with severe heart disease, psychosis, or cirrhosis. Monitor LFTs and CBC at baseline and periodically. Disulfiram may also inhibit CYP450 enzymes (CYP2E1, CYP1A2, CYP3A4), potentiating warfarin, phenytoin, and theophylline. Onset of aversion therapy requires 12-48 hours after the last alcohol dose; maintain alcohol-free period of 24 hours before starting. Duration of action persists up to 14 days after discontinuation. Inadvertent alcohol exposure in topical products (mouthwash, colognes) can trigger reactions.
ACTIQ is a transmucosal immediate-release fentanyl formulation indicated for breakthrough cancer pain in opioid-tolerant patients. Initiate with the lowest strength (200 mcg) and titrate upward. Avoid use in opioid-naive patients due to risk of fatal respiratory depression. Place the unit between cheek and lower gum, not sublingually. Instruct patient not to bite or suck the unit. Monitor for sedation and respiratory depression. Multiple units may be used per episode if needed, but wait at least 4 hours before next episode. Dispose of partially used units by flushing down toilet.
Avoid all forms of alcohol, including beverages, mouthwash, cough syrup, cooking wine, vinegar, aftershave, and hand sanitizers.,Reaction to alcohol includes severe flushing, nausea, vomiting, chest pain, difficulty breathing, and blurred vision; seek emergency care if symptoms occur.,The disulfiram-alcohol reaction can be fatal even with small amounts of alcohol.,Inform all healthcare providers (including dentists) that you are taking disulfiram.,Reactions may occur up to 14 days after stopping the medication.,Do not take disulfiram if you have recently consumed alcohol; wait at least 12 hours after the last drink.,Carry a medical alert card or wear a bracelet stating you are on disulfiram.,Report any signs of liver toxicity: yellowing of eyes/skin, dark urine, severe fatigue.
Only use ACTIQ if you are already taking regular around-the-clock opioid pain medicine and are tolerant to opioids.,Do not use ACTIQ for short-term pain like after surgery, headache, or dental pain.,Place the unit in your cheek pouch, not under your tongue. Do not chew or suck it.,If you need more than 4 units per day, contact your doctor as your dose may need adjustment.,Store ACTIQ in a safe place away from children, as accidental ingestion can be fatal.,Dispose of unused or partially used units by flushing them down the toilet.
"Rifapentine, a potent inducer of cytochrome P450 enzymes, significantly increases the metabolism of disulfiram by inducing hepatic CYP3A4 and other metabolic pathways. This induction reduces disulfiram plasma concentrations, potentially diminishing its therapeutic efficacy in maintaining alcohol aversion. The interaction may lead to an increased risk of alcohol consumption relapse and associated clinical consequences."
"Disulfiram inhibits aldehyde dehydrogenase, leading to acetaldehyde accumulation, but also inhibits CYP3A4 and other CYP enzymes. Palbociclib is primarily metabolized by CYP3A4 and is a substrate of this enzyme. Coadministration with disulfiram can significantly increase palbociclib serum concentrations, raising the risk of dose-dependent toxicities such as neutropenia, infections, and fatigue."
"Disulfiram irreversibly inhibits aldehyde dehydrogenase and also suppresses the activity of cytochrome P450 (CYP) 2D6 and other CYP enzymes, thereby reducing the hepatic metabolism of venlafaxine. This can lead to increased plasma concentrations of venlafaxine and its active metabolite O-desmethylvenlafaxine, elevating the risk of dose-dependent adverse effects such as hypertension, nausea, dizziness, and serotonin syndrome. Additionally, disulfiram's own metabolism may be affected, potentially increasing the severity of disulfiram-ethanol reactions."
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about DISULFIRAM vs ACTIQ, answered by our medical review team.
DISULFIRAM is a Aldehyde Dehydrogenase Inhibitor that works by Disulfiram irreversibly inhibits aldehyde dehydrogenase, causing accumulation of acetaldehyde after alcohol ingestion, leading to aversive effects such as flushing, nausea, and hypotension.. ACTIQ is a Opioid Analgesic that works by Opioid agonist; binds to mu-opioid receptors in the CNS, altering pain perception and response.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between DISULFIRAM and ACTIQ depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of DISULFIRAM is: 250 mg orally once daily, increased to 500 mg orally once daily if needed; maintenance dose typically 250 mg per day (range 125-500 mg).. The standard adult dose of ACTIQ is: 200 mcg transmucosally, titrated upward as needed; initial dose for opioid-tolerant patients is 200 mcg, with additional doses possible after 15 minutes if needed. Maximum 4 doses per episode. At least 4 hours between episodes.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between DISULFIRAM and ACTIQ in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. DISULFIRAM is classified as Category C. Pregnancy Category C. First trimester: Limited human data; animal studies show embryotoxic effects at high doses. Avoid unless benefit outweighs risk. Second and third trimesters: . ACTIQ is classified as Category C. FDA Pregnancy Category C. First trimester: limited human data; animal studies show increased resorptions and fetal growth restriction. Second/third trimester: chronic use may cause. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.