Treats muscle spasms caused by multiple sclerosis, cerebral palsy, or damage to your brain or spinal cord. Also used to treat and prevent symptoms of malignant hyperthermia (an inherited muscle disorder) in people who are at risk.
There may be other brand names for this medicine.
When This Medicine Should Not Be Used
You should not use this medicine if you have had an allergic reaction to dantrolene, or if you have active liver disease (especially hepatitis or cirrhosis). This medicine should not be used to treat muscle spasms caused by rheumatic disorders.
How to Use This Medicine
- Your doctor will tell you how much of this medicine to use and how often. Your dose may need to be changed several times in order to find out what works best for you. Do not use more medicine or use it more often than your doctor tells you to.
If a dose is missed:
- If you miss a dose or forget to use your medicine, use it as soon as you can. If it is almost time for your next dose, wait until then to use the medicine and skip the missed dose. Do not use extra medicine to make up for a missed dose.
How to Store and Dispose of This Medicine
- Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
- Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any outdated medicine or medicine no longer needed.
- Keep all medicine away from children and never share your medicine with anyone.
Drugs and Foods to Avoid
Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.
- Tell your doctor if you are using any medicines that make you sleepy. These include sleeping pills, cold and allergy medicine, narcotic pain relievers, and sedatives.
- Make sure your doctor knows if you are also using any other medicine to treat your MS, cerebral palsy, or related muscle problems. Tell your doctor if you are using a medicine that contains estrogen (such as birth control pills, Estratest®, or Premarin®), or if you are using a heart or blood pressure medicine (such as diltiazem, nifedipine, verapamil, Adalat®, Calan®, Cardizem®, Cartia®, Lotrel®, Procardia®, or Tiazac®).
Warnings While Using This Medicine
- Tell your doctor if you are pregnant or breast feeding, or if you have a history of liver disease, heart disease, asthma, or any other breathing problems.
- Your doctor will need to check your progress at regular visits while you are using this medicine. Be sure to keep all appointments.
- Make sure any doctor or dentist who treats you knows that you are using this medicine. This medicine may affect the results of certain medical tests.
- This medicine may make you dizzy or drowsy. Avoid driving, using machines, or doing anything else that could be dangerous if you are not alert.
- This medicine may make your skin more sensitive to sunlight. Use a sunscreen when you are outdoors. Avoid sunlamps and tanning beds.
Possible Side Effects While Using This Medicine
Call your doctor right away if you notice any of these side effects:
- Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
- Chest pain, or uneven heartbeat.
- Dark-colored urine, or pale stools.
- Nausea, vomiting, loss of appetite, or pain in your upper stomach.
- Severe diarrhea.
- Shortness of breath, or coughing up blood.
- Skin or whites of your eyes turn yellow.
- Slurred speech, or trouble speaking.
If you notice these less serious side effects, talk with your doctor:
- Change in how much or how often you urinate.
- Dizziness, drowsiness, or light-headedness.
- Mild diarrhea, or constipation.
- Muscle pain or weakness.