Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
ACTIQ vs BAL
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Opioid agonist; binds to mu-opioid receptors in the CNS, altering pain perception and response.
Chelating agent that forms stable complexes with heavy metals (e.g., arsenic, mercury, lead) by binding to their sulfhydryl groups, facilitating renal excretion.
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
Arsenic poisoning,Mercury poisoning,Lead poisoning (adjunct to edetate calcium disodium),Acute gold poisoning,Wilson's disease (investigational)
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.
3-5 mg/kg IM every 4 hours for 2 days, then every 6 hours for 1 day, then every 12 hours for 10 days.
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.
Terminal elimination half-life is approximately 6.8 hours (range 4–13 hours). In patients with impaired renal function, half-life may be prolonged.
Primarily hepatic via CYP3A4 to inactive metabolites (norfentanyl, despropionylfentanyl, hydroxyfentanyl) and other metabolites; <7% excreted unchanged in urine.
Primarily hepatic; undergoes oxidation and conjugation; metabolites excreted renally.
Primarily renal as metabolites (about 75% as metabolites, <10% unchanged). Fecal excretion accounts for <9%. Biliary excretion is minor.
Primarily renal; approximately 80% of a dose is excreted in urine as unchanged drug and metabolites within 24 hours. Biliary/fecal elimination accounts for less than 5%.
Fentanyl is 80–85% bound to plasma proteins (primarily albumin and α1-acid glycoprotein).
BAL is extensively bound to plasma proteins, primarily albumin, with protein binding >90%.
Approximately 4 L/kg (range 3–6 L/kg); large Vd indicates extensive tissue distribution and redistribution contributing to short duration.
Volume of distribution is approximately 3.5 L/kg, indicating extensive distribution into tissues, including brain and intracellular spaces.
Oral transmucosal: 50% (range 47–54%) relative to IV; variable and enhanced by rapid absorption through buccal mucosa.
BAL is not administered orally due to poor absorption and gastrointestinal irritation. Given intravenously, bioavailability is 100%. Intramuscular bioavailability is similar but with slower absorption.
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.
GFR 10-50 m L/min: reduce frequency to every 6-8 hours; GFR <10 m L/min: reduce frequency to every 8-12 hours.
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.
Child-Pugh A: no adjustment; Child-Pugh B: reduce dose by 25%; Child-Pugh C: reduce dose by 50% and monitor for hepatotoxicity.
Not approved for pediatric use; safety and efficacy not established in patients under 16 years.
3-5 mg/kg IM every 4 hours for 2 days, then every 6 hours for 1 day, then every 12 hours for 10 days; maximum 100 mg per dose.
Initiate at 100 mcg transmucosally; titrate slowly due to increased sensitivity and risk of respiratory depression. Monitor for adverse effects.
Start at 3 mg/kg IM every 6 hours; adjust based on renal function, monitor for hypotension and pain at injection site.
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.
None.
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.
Monitor renal function and serum electrolytes during therapy.,Can cause hypertension, tachycardia, and myocardial ischemia; use cautiously in cardiovascular disease.,May induce hemolytic anemia in patients with G6PD deficiency.,Injection site reactions and sterile abscesses may occur.,Iron deficiency is a known adverse effect due to iron chelation.
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.
Hypersensitivity to BAL or any component.,Hepatic insufficiency (unless benefit outweighs risk).,Iron poisoning (forms toxic complex).,Concurrent use with cadmium or selenium (increased toxicity).
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.
Avoid alcohol and caffeine. Maintain adequate hydration. No specific food restrictions, but ensure iron-rich foods are avoided if concurrent iron poisoning suspected (though BAL not indicated for iron).
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.
Insufficient human data; animal studies suggest potential teratogenicity at high doses. Avoid in first trimester unless benefit outweighs risk.
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.
BAL (dimercaprol) is excreted into breast milk; M/P ratio unknown. Limited data; exercise caution and consider temporary cessation of breastfeeding during therapy.
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.
No specific dose adjustments recommended in pregnancy; monitor for increased volume of distribution and potential need for higher doses if toxicity persists.
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.
BAL (dimercaprol) is used as a chelating agent for heavy metal poisoning, particularly arsenic, lead, and mercury. Administer deep IM only; avoid IV due to risk of hemolysis. Monitor blood pressure closely as hypertension can occur. Contraindicated in peanut allergy due to peanut oil vehicle. Administer with alkaline urine to protect kidneys.
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.
This medication is given as an injection into a muscle.,You may experience a metallic taste, headache, or nausea.,Report any signs of allergic reaction such as rash or difficulty breathing.,Avoid alcohol while on this medication.,Do not drive or operate heavy machinery until you know how this drug affects you.
No interactions on record
"Pregabalin, a gabapentinoid, enhances the inhibitory effects of GABA by binding to the α2δ subunit of voltage-gated calcium channels, reducing excitatory neurotransmitter release. Dapiprazole, an α1-adrenoceptor antagonist used for miosis, can have its therapeutic efficacy increased when combined with pregabalin due to additive central nervous system depression. This interaction may result in enhanced sedation, dizziness, and psychomotor impairment, potentially increasing the risk of falls and cognitive dysfunction."
"Pregabalin and pravastatin may exhibit an additive risk of musculoskeletal adverse effects, particularly myopathy and rhabdomyolysis, due to their overlapping effects on muscle cells. Pregabalin can cause dose-related muscle damage, while pravastatin inhibits HMG-CoA reductase, leading to reduced skeletal muscle integrity. This combination may potentiate serum creatine kinase elevations and increase the likelihood of clinical myopathy, especially in patients with predisposing factors such as renal impairment or concomitant use of other myotoxic agents."
"Pregabalin may cause fluid retention and peripheral edema, which can precipitate or exacerbate heart failure, especially in patients with pre-existing cardiac risk factors. Rosiglitazone, a thiazolidinedione, also promotes fluid retention and increases plasma volume via PPAR-γ-mediated renal effects. When combined, the additive fluid-retaining properties of both drugs can synergistically elevate the risk of new-onset or worsening heart failure, particularly in patients with reduced left ventricular function or NYHA Class III/IV status."
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about ACTIQ vs BAL, answered by our medical review team.
ACTIQ is a Opioid Analgesic that works by Opioid agonist; binds to mu-opioid receptors in the CNS, altering pain perception and response.. BAL is a Chelating Agent that works by Chelating agent that forms stable complexes with heavy metals (e.g., arsenic, mercury, lead) by binding to their sulfhydryl groups, facilitating renal excretion.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between ACTIQ and BAL 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 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.. The standard adult dose of BAL is: 3-5 mg/kg IM every 4 hours for 2 days, then every 6 hours for 1 day, then every 12 hours for 10 days.. 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 ACTIQ and BAL 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. 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. BAL is classified as Category C. Insufficient human data; animal studies suggest potential teratogenicity at high doses. Avoid in first trimester unless benefit outweighs risk.. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.