Home > Medical Reference > Encyclopedia (English)

Please install flash player to see this video.

Hospital Virtual Tour

Related Content

Pronunciation:

(DAN troe leen)

U.S. Brand Names:

Dantrium®

Synonyms:

Dantrolene Sodium

Generic Available:

Canadian Brand Names:

Dantrium®

Use:

Treatment of spasticity associated with spinal cord injury, stroke, cerebral palsy, or multiple sclerosis; treatment of malignant hyperthermia

Use - Unlabeled/Investigational:

Neuroleptic malignant syndrome (NMS)

Pregnancy Risk Factor:

Lactation:

Excretion in breast milk unknown/not recommended

Contraindications:

Active hepatic disease; should not be used where spasticity is used to maintain posture or balance

Warnings/Precautions:

Use with caution in patients with impaired cardiac function or impaired pulmonary function; has potential for hepatotoxicity; overt hepatitis has been most frequently observed between the third and twelfth month of therapy; hepatic injury appears to be greater in females and in patients >35 years of age

Adverse Reactions:

>10%:

Central nervous system: Drowsiness, dizziness, lightheadedness, fatigue

Dermatologic: Rash

Gastrointestinal: Diarrhea (mild), nausea, vomiting

Neuromuscular & skeletal: Muscle weakness

1% to 10%:

Cardiovascular: Pleural effusion with pericarditis

Central nervous system: Chills, fever, headache, insomnia, nervousness, mental depression

Gastrointestinal: Diarrhea (severe), constipation, anorexia, stomach cramps

Ocular: Blurred vision

Respiratory: Respiratory depression

<1%: Seizures, confusion, hepatitis, hepatic necrosis

Overdosage/Toxicology:

Symptoms of overdose include CNS depression, hypotension, nausea, and vomiting. For decontamination, lavage with activated charcoal and administer a cathartic. Do not use ipecac. Other treatment is supportive and symptomatic.

Drug Interactions:

Substrate of CYP3A4 (major)

CYP3A4 inducers: CYP3A4 inducers may decrease the levels/effects of dantrolene. Example inducers include aminoglutethimide, carbamazepine, nafcillin, nevirapine, phenobarbital, phenytoin, and rifamycins.

CYP3A4 inhibitors: May increase the levels/effects of dantrolene. Example inhibitors include azole antifungals, ciprofloxacin, clarithromycin, diclofenac, doxycycline, erythromycin, imatinib, isoniazid, nefazodone, nicardipine, propofol, protease inhibitors, quinidine, and verapamil.

Increased toxicity: Estrogens (hepatotoxicity), CNS depressants (sedation), MAO inhibitors, phenothiazines, clindamycin (increased neuromuscular blockade), verapamil (hyperkalemia and cardiac depression), warfarin, clofibrate, and tolbutamide

Ethanol/Nutrition/Herb Interactions:

Ethanol: Avoid ethanol (may increase CNS depression).

Herb/Nutraceutical: Avoid valerian, St John's wort, kava kava, gotu kola (may increase CNS depression).

Stability:

Reconstitute vial by adding 60 mL of sterile water for injection USP (not bacteriostatic water for injection); protect from light; use within 6 hours; avoid glass bottles for I.V. infusion

Mechanism of Action:

Acts directly on skeletal muscle by interfering with release of calcium ion from the sarcoplasmic reticulum; prevents or reduces the increase in myoplasmic calcium ion concentration that activates the acute catabolic processes associated with malignant hyperthermia

Pharmacodynamics/Kinetics:

Absorption: Oral: Slow and incomplete

Metabolism: Hepatic

Half-life elimination: 8.7 hours

Excretion: Feces (45% to 50%); urine (25% as unchanged drug and metabolites)

Dosage:

Spasticity: Oral:

Children: Initial: 0.5 mg/kg/dose twice daily, increase frequency to 3-4 times/day at 4- to 7-day intervals, then increase dose by 0.5 mg/kg to a maximum of 3 mg/kg/dose 2-4 times/day up to 400 mg/day

Adults: 25 mg/day to start, increase frequency to 2-4 times/day, then increase dose by 25 mg every 4-7 days to a maximum of 100 mg 2-4 times/day or 400 mg/day

Malignant hyperthermia: Children and Adults:

Preoperative prophylaxis:

Oral: 4-8 mg/kg/day in 4 divided doses, begin 1-2 days prior to surgery with last dose 3-4 hours prior to surgery

I.V.: 2.5 mg/kg ~1¹/4 hours prior to anesthesia and infused over 1 hour with additional doses as needed and individualized

Crisis: I.V.: 2.5 mg/kg; may repeat dose up to cumulative dose of 10 mg/kg; if physiologic and metabolic abnormalities reappear, repeat regimen

Postcrisis follow-up: Oral: 4-8 mg/kg/day in 4 divided doses for 1-3 days; I.V. dantrolene may be used when oral therapy is not practical; individualize dosage beginning with 1 mg/kg or more as the clinical situation dictates

Neuroleptic malignant syndrome (unlabeled use): I.V.: 1 mg/kg; may repeat dose up to maximum cumulative dose of 10 mg/kg, then switch to oral dosage

Administration:

I.V.: Therapeutic or emergency dose can be administered with rapid continuous I.V. push. Follow-up doses should be administered over 2-3 minutes.

Monitoring Parameters:

Motor performance should be monitored for therapeutic outcomes; nausea, vomiting, and liver function tests should be monitored for potential hepatotoxicity; intravenous administration requires cardiac monitor and blood pressure monitor

Patient Education:

Take exactly as directed. Do not increase dose or discontinue without consulting prescriber. Do not use alcohol, prescriptive or OTC antidepressants, sedatives, or pain medications without consulting prescriber. You may experience drowsiness, dizziness, lightheadedness (avoid driving or engaging in tasks that require alertness until response to drug is known); nausea or vomiting (small, frequent meals, frequent mouth care, or sucking hard candy may help); or diarrhea (buttermilk, boiled milk, or yogurt may help). Report excessive confusion; drowsiness or mental agitation; chest pain, palpitations, or respiratory difficulty; skin rash; or vision changes. Pregnancy/breast-feeding precautions: Inform prescriber if you are or intend to become pregnant. Breast-feeding is not recommended.

Dental Health: Effects on Dental Treatment:

No significant effects or complications reported

Dental Health: Vasoconstrictor/Local Anesthetic Precautions:

No information available to require special precautions

Mental Health: Effects on Mental Status:

Drowsiness is common; may cause insomnia, nervousness, confusion, or depression

Mental Health: Effects on Psychiatric Treatment:

Concurrent use with psychotropic may result in additive sedation; use to treat neuroleptic malignant syndrome

Dosage Forms:

Capsule, as sodium: 25 mg, 50 mg, 100 mg

Injection, powder for reconstitution, as sodium: 20 mg [contains mannitol 3 g]

Extemporaneously Prepared:

A 5 mg/mL suspension may be made by adding five 100 mg capsules to a citric acid solution (150 mg citric acid powder in 10 mL water) and then adding syrup to a total volume of 100 mL; stable 2 days in refrigerator

Nahata MC and Hipple TF, Pediatric Drug Formulations, 1st ed, Cincinnati, OH: Harvey Whitney Books Co, 1990.

International Brand Names:

Dantamacrin® (CH, DE); Dantrium® (AU, BE, CA, CL, DK, FR, GB, HK, IE, IL, IT, JP, LU, NL, NZ, PT, ZA); Dantrium Intravenoso® (CL); Dantrium Intravenous® (GB); Dantrolen® (AR, AT, BR, CH, CZ, DE, HU, PL)

References

Britt BA, "Dantrolene,"Can J Anaesth, 1984, 31(1):61-75.

Guerrero RM and Shifrar KA, "Diagnosis and Treatment of Neuroleptic Malignant Syndrome,"Clin Pharm, 1988, 7(9):697-701.

May DC, Morris SW, Stewart RM, et al, "Neuroleptic Malignant Syndrome: Response to Dantrolene Sodium,"Ann Intern Med, 1983, 98(2):183-4.

Nahata MC and Hipple TF, Pediatric Drug Formulations, 1st ed, Harvey Whitney Books Co, 1990.

Paloucek FP, Erickson TE, Lundquist S, et al, "Oral Dantrolene Ingestion: A Case Series (Abstract),"Vet Hum Toxicol, 1991, 33:362.

Rosenberg MR and Green M, "Neuroleptic Malignant Syndrome. Review of Response to Therapy,"Arch Intern Med, 1989, 149(9):1927-31.

Rubin AS and Zablocki AD, "Hyperkalemia, Verapamil, and Dantrolene,"Anesthesiology, 1987, 66(2):248-9.

Tayeb OS, "A Serious Interaction of Dantrolene and Theophylline,"Vet Hum Toxicol, 1990, 32(5):442-3.

Ward A, Chaffman MO, and Sorkin EM, "Dantrolene: A Review of Its Pharmacodynamic and Pharmacokinetic Properties and Therapeutic Use in Malignant Hyperthermia, the Neuroleptic Malignant Syndrome and an Update of Its Use in Muscle Spasticity,"Drugs, 1986, 32(2):130-68.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.