Muscle fatigue
Muscle fatigue

Tensilon test

Definition:
In this test, the drug Tensilon is administered, and muscle response is evaluated to help diagnose myasthenia gravis (a chronic, progressive disease characterized by weakness of the voluntary muscles).

How the test is performed:
The drug Tensilon is slowly given through an intravenous line. The health care provider may want to fatigue your muscles by having you do various exercises such as counting to 100 until your voice diminishes, or holding your arms above your shoulders until they drop. The rest of the Tensilon is then given. You will be asked to perform some repetitive muscular movements like crossing and uncrossing your legs with particular attention paid to whether your muscle strength is improved by the Tensilon. The test may be repeated and additional Tensilon may be given to help differentiate between myasthenia gravis and other conditions.
How to prepare for the test:
There may be no preparations, however you should follow any diet or directions prescribed by your health care provider.
How the test will feel:
There will be a sharp prick as the IV needle is inserted. There may be some side effects from the drug.
Why the test is performed:
The test helps diagnosis myasthenia gravis, may aid in differentiation between myasthenic and other similar neurological conditions, and may be used to monitor oral anticholinesterase therapy.
What abnormal results mean:
In myasthenia gravis, the muscles will improve immediately following the Tensilon. The maximum benefit only lasts several minutes. In myasthenic crisis (exacerbation of the disease that requires anticholinesterase therapy), there is a brief improvement in the muscle strength. In cholinergic crisis (overdose of anticholinesterase), the Tensilon will exaggerate the muscle weakness.

Additional conditions under which the test may be performed:
What the risks are:
The risks are side effects from the drug, including respiratory failure.

Review Date: 11/21/2001
Reviewed By: Steven Angelo, M.D., Department of Internal Medicine, Yale School of Medicine, Hospital of Saint Raphael, New Haven, CT. Review provided by VeriMed Healthcare Network.
A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is the first of its kind, requiring compliance with 53 standards of quality and accountability, verified by independent audit. A.D.A.M. is among the first to achieve this important distinction for online health information and services. A.D.A.M. is also a founding member of Hi-Ethics (www.hiethics.com) and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 2003 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.