Indication
Muscle tightness, muscle cramping (spasms), muscle pain caused by spinal cord injury, stroke, cerebral palsy, multiple sclerosis.
Administration
May be taken with or without food.
Adult Dose
Oral
Spasticity
Adult: Initially, 25 mg daily increased gradually at 7-day intervals over 7 wk. Discontinue if no response after 45 days of treatment. Max: 100 mg 4 times daily.
Child Dose
Oral
Spasticity
Child: Initially, 0.5 mg/kg once daily, may increase gradually to 2 mg/kg 3-4 times daily. Max: 100 mg 4 times daily.
Contraindication
Active liver disease; acute muscle spasm; patients who use their spasticity to maintain posture or function. Lactation.
Mode of Action
Dantrolene has a direct action on skeletal muscle. It uncouples muscular contraction from excitation, probably by interfering with calcium release from sarcoplasmic reticulum.
Precaution
Perform LFTs before and during treatment. Increased risk of liver injury in patients >30 yr, female patients especially those on oestrogen therapy, history of liver disease or patients with daily dose >400 mg. Cardiac or pulmonary disorders. Pregnancy.
Lactation: enters breast milk/not recommended
Side Effect
Fatigue, muscle weakness/pain. GI disturbances, CNS effects, tachycardia, unstable BP, dyspnoea, drowsiness, rashes, pruritus, chills and fever, visual disturbances, dysphagia, speech disturbances; haematuria, crystalluria, urinary frequency, retention and incontinence. Increased serum AST (SGOT), ALT (SGPT), alkaline phosphatase, LDH, BUN, and total serum bilirubin concentrations, Difficult erection, Abnormal hair growth, Aplastic anemia, Anemia, Leukopenia, Lymphoma, Thrombocytopenia
Potentially Fatal: Hepatotoxicity, pleural effusion with pericarditis.
Pregnancy Category Note
Pregnancy Category: C
Lactation: enters breast milk/not recommended
Interaction
CNS depressants; oestrogens; calcium-channel blockers. CNS effects enhanced by alcohol or CNS depressants.