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Generic Name: ambenonium (AM-be-NOE-nee-um)
Brand Name: Mytelase

Mytelase is used for:

Treating myasthenia gravis. It may also be used for other conditions as determined by your doctor.

Mytelase is a cholinesterase inhibitor. It works by improving nerve impulses in muscles so that the muscles are better able to work.

Do NOT use Mytelase if:

  • you are allergic to any ingredient in Mytelase
  • you are taking quinine, quinidine, atropine, belladonna, ganglionic blocking agents (eg, mecamylamine), or cholinergic agents (eg, guanidine)

Contact your doctor or health care provider right away if any of these apply to you.

Before using Mytelase:

Some medical conditions may interact with Mytelase. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

  • if you are pregnant, planning to become pregnant, or are breast-feeding
  • if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
  • if you have allergies to medicines, foods, or other substances
  • if you have heart problems (eg, heart block, slow heartbeat); Parkinson disease; a urinary tract infection; asthma; kidney problems; or a blockage of your stomach, bowel, or bladder

Some MEDICINES MAY INTERACT with Mytelase. Tell your health care provider if you are taking any other medicines, especially any of the following:

  • Atropine, belladonna, ganglionic blocking agents (eg, mecamylamine), quinine, or quinidine because effectiveness of Mytelase may be decreased
  • Cholinergic agents (eg, guanidine) because the risk of side effects may be increased

This may not be a complete list of all interactions that may occur. Ask your health care provider if Mytelase may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

How to use Mytelase:

Use Mytelase as directed by your doctor. Check the label on the medicine for exact dosing instructions.

  • Take Mytelase by mouth with or without food. If stomach upset occurs, take with food to reduce stomach irritation.
  • If you miss a dose of Mytelase, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.

Ask your health care provider any questions you may have about how to use Mytelase.

Important safety information:

  • Tell your doctor or dentist that you take Mytelase before you receive any medical or dental care, emergency care, or surgery.
  • Do not change your dose without checking with your doctor.
  • Mytelase should be used with extreme caution in CHILDREN; safety and effectiveness in children have not been confirmed.
  • PREGNANCY and BREAST-FEEDING: If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of using Mytelase while you are pregnant. It is not known if this medicine is found in breast milk. Do not breast-feed while taking Mytelase.

Possible side effects of Mytelase:

All medicines may cause side effects, but many people have no, or minor, side effects. When used in small doses, no COMMON side effects have been reported with this product. Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); diarrhea; fainting; increased production of saliva or tears; increased sweating; muscle cramps, twitching, or weakness; nausea; small pupils; stomach cramps; tremor; trouble speaking or swallowing; unusual tiredness with anxiety and dizziness or light-headedness; urgent urination; vision changes; vomiting; weakness.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088. You may also report side effects at .

If OVERDOSE is suspected:

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately. Symptoms may include diarrhea; dizziness or light-headedness; fainting; frequent or urgent urination; increased production of saliva; increased sweating; muscle twitching, weakness, or paralysis; nausea; pale skin; panic; severe anxiety; severe headache; slow heartbeat; small pupils; stomach cramps; tremor; trouble breathing; trouble speaking or swallowing; unusual tiredness; vision changes (eg, blurred vision); vomiting; weakness.

Proper storage of Mytelase:

Store Mytelase at room temperatures up to 77 degrees F (25 degrees C). Store away from heat, moisture, and light. Do not store in the bathroom. Keep Mytelase out of the reach of children and away from pets.

General information:

  • If you have any questions about Mytelase, please talk with your doctor, pharmacist, or other health care provider.
  • Mytelase is to be used only by the patient for whom it is prescribed. Do not share it with other people.
  • If your symptoms do not improve or if they become worse, check with your doctor.
  • Check with your pharmacist about how to dispose of unused medicine.

This information should not be used to decide whether or not to take Mytelase or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about Mytelase. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to Mytelase. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using Mytelase.

Issue Date: June 3, 2015

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.