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Generic name: edrophonium [ ED-roe-FOE-nee-um ]
Brand names: Enlon, Reversol, Tensilon
Drug class: Cholinergic muscle stimulants

What is edrophonium?

Edrophonium is used as part of a medical test to help diagnose a muscle disorder called myasthenia gravis.

Edrophonium is sometimes used to reverse the effects of certain medications used to prevent muscle contractions during surgical procedures.

Edrophonium may also be used for purposes not listed in this medication guide.

Important Information

You should not receive edrophonium if you have a blockage in your intestines, or if you are unable to urinate.

Before taking this medicine

You should not receive edrophonium if you are allergic to it, or if you have:

  • a blockage in your intestines; or

  • if you are unable to urinate.

To make sure edrophonium is safe for you, tell your doctor if you have:

  • asthma;

  • a heart rhythm disorder; or

  • if you are allergic to sulfites.

It is not known whether edrophonium will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using edrophonium.

Do not receive this medication without telling your doctor if you are breast-feeding a baby.

How is edrophonium given?

Edrophonium is injected into a muscle, or into a vein through an IV. A healthcare provider will give you this injection.

When used in testing for myasthenia gravis, edrophonium is given in small doses over 15 to 45 seconds. After each dose you will be observed for certain reactions to this medicine (muscle twitching, vision changes, increased muscle weakness, sweating, stomach cramps, nausea, and other symptoms). You may receive other medications to treat the reaction to edrophonium.

The test you are receiving may be repeated a second time.

Your specific edrophonium test may be performed in a different manner than described above.

What happens if I miss a dose?

Since edrophonium is given by a healthcare professional, it is not likely that you will miss a dose.

What happens if I overdose?

Since edrophonium is given by a healthcare professional in a medical setting, an overdose is unlikely to occur.

What should I avoid after receiving edrophonium?

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

Edrophonium side effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Tell your caregivers right away if you have:

  • slow heartbeats, weak or shallow breathing, feeling like you might pass out;

  • vision problems, eye redness or watering;

  • seizure (convulsions);

  • trouble speaking or swallowing;

  • cough with mucus, wheezing, feeling short of breath;

  • increased salivation, nausea, vomiting, diarrhea, stomach pain;

  • muscle weakness, twitching or involuntary movement;

  • increased sweating, urinating more than usual; or

  • loss of bowel or bladder control.

Common side effects (some of which can be expected as part of a positive test reaction) may include:

  • watery eyes, vision problems;

  • changes in your voice;

  • mild nausea, vomiting, diarrhea, stomach pain;

  • weakness; or

  • muscle twitching.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect edrophonium?

Other drugs may interact with edrophonium, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Where can I get more information?

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Further information

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