Dantrolene sodium is a drug used to treat chronic, severe spasticity and spasms. The NICE guideline states that dantrolene can be used if treatment with baclofen (Lioresal) or gabapentin has not been successful.
Dantrolene works by stopping some electrical impulses travelling within muscles, thereby preventing muscle contractions. This contrasts with most other spasticity drugs that work by preventing or inhibiting the way the brain and spinal cord communicate through the nerves with the rest of the body.
Dantrolene sodium is taken orally as tablets. Dosage varies but should not exceed 400mg per day.
Side effects include drowsiness, dizziness, weakness and fatigue. All of these may be temporary. Another side effect you may experience is diarrhoea, which can be severe. Dantrolene should not be taken by people with a history of liver dysfunction, or by pregnant or breastfeeding women.
Liver function tests should be carried out before starting and frequently during treatment as there is a risk of liver damage (known as hepatotoxicity).
