What special precautions should I follow?  

Before taking dantrolene,

• tell your doctor and pharmacist if you are allergic to dantrolene or any other drugs.
• tell your doctor and pharmacist what prescription and nonprescription medications you are taking, especially diazepam (Valium); estrogen; medications for seizures, allergies, colds, or coughs; sedatives; sleeping pills; tranquilizers; and vitamins.
• tell your doctor if you have or have ever had liver, heart, rheumatic, or lung disease.
• tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking dantrolene, call your doctor immediately.
• you should know that this drug may make you drowsy. Do not drive a car or operate machinery until you know how dantrolene affects you.
• remember that alcohol can add to the drowsiness caused by this drug.
• you should plan to avoid unnecessary or prolonged exposure to sunlight and to wear protective clothing, sunglasses, and sunscreen. Dantrolene may make your skin sensitive to sunlight.

What should I do if I forget a dose?     

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for the missed one.