Version July 2025
| Medication | Mechanism | Usual dosing | Adverse effects | |||
| Age group | Starting dose | Titration | Maximum dose | |||
| Baclofen | Centrally acting, GABA-B agonist | Adults | 5 mg once daily | 5 mg per dose every 3 to 7 days | 80 mg per day; some patients may require up to 120 mg per day | Gastrointestinal: constipation, nausea, vomiting. Genitourinary: urinary retention. Neurologic: ataxia, confusion, dizziness, hypotonia, paresthesias, sedation, weakness. A withdrawal syndrome (eg, seizures, hallucinations, rebound spasticity, high fever, hypertension) may occur with abrupt discontinuation. |
| Adolescents and children ≥8 years | 5 mg 2 or 3 times daily | 5 mg per dose every 7 days | 60 mg per day; higher doses may be administered with close monitoring | |||
| Children 2 to <8 years | 0.5 mg/kg per day in 2 or 3 divided doses (maximum: 2.5 mg/dose) | 0.5 mg/kg per day every 7 days | 2 mg/kg per day (40 mg per day; doses up to 60 mg per day have been reported) | |||
| Diazepam | Centrally acting, GABA-A agonist | Adults and adolescents >12 years | 2 mg once or twice daily or 5 mg at bedtime | May increase in increments of 2 to 5 mg per day every 7 days | 40 to 60 mg per day in 3 or 4 divided doses | Neurologic: ataxia, cognitive impairment (eg, memory disturbances), dizziness, sedation. Neuromuscular: asthenia. Potential for dependence. A withdrawal syndrome (eg, agitation, psychosis, seizures) may occur with abrupt discontinuation. |
| Children ≥6 months to 12 years | 0.01 to 0.3 mg/kg in 2 to 4 divided doses (maximum: 2 mg/dose) | May increase in increments of 0.1 to 0.3 mg/kg (maximum 10 mg) per day every 7 days | 20 to 40 mg per day (not to exceed 10 mg per dose) | |||
| Dantrolene | Peripherally acting, inhibits calcium release from sarcoplasmic reticulum of the muscle | Adults, adolescents, and children (≥5 years) who weigh ≥50 kg | 25 mg once daily | Every 7 days as follows:
Some patients may require 100 mg 4 times daily | 100 mg 4 times daily | Potentially irreversible hepatotoxicity requires regular monitoring; stop therapy if benefits are not evident within 45 days. Use the lowest dose associated with optimal response. Gastrointestinal: diarrhea, nausea. Neurologic: drowsiness, lethargy, paresthesias, weakness. |
| Adolescents and children (≥5 years) who weigh <50 kg | 0.5 mg/kg/dose once or twice daily | Every 7 days as follows:
Some patients may require 2 mg/kg/dose 4 times daily | 2 mg/kg/dose 4 times daily (not to exceed 100 mg per dose or 400 mg per day) | |||
| Tizanidine | Centrally acting, alpha-2 adrenergic agonist | Adults | 2 mg once daily at bedtime For spasticity associated with certain comorbidities (eg, ALS, stroke), may start with 2 mg 2 to 3 times daily | May increase in increments of 2 to 4 mg per day every 3 to 7 days | 36 mg per day in 3 or 4 divided doses For patients with ALS, doses >24 mg per day may not confer additional benefit | Cardiovascular: hypotension. Gastrointestinal: vomiting, xerostomia. Hepatic: reversible elevation of transaminase, liver injury ranging from hepatitis to acute liver failure. Neurologic: dizziness, drowsiness, fatigue, sedation, weakness. A withdrawal syndrome (eg, dysthermia, hallucinations, hypertension, nausea, tremor, and tachycardia) may occur with abrupt discontinuation. |
| Adolescents and children ≥10 years | 2 mg once daily at bedtime | May increase in increments of 2 to 4 mg per day every 3 to 7 days | 24 mg per day in 3 to 4 divided doses | |||
| Children 2 to <10 years | 1 mg once daily at bedtime | May increase in increments of 2 to 4 mg per day every 3 to 7 days | 24 mg per day in 3 to 4 divided doses | |||
Prepared with data from: UpToDate Lexidrug. More information available at https://online.lexi.com/.
