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Anesthesiology/Topical Eye Anesthetic in Malignant Hyperthermia


Good evening Dr. Porter,

Is it safe for someone with a family history of malignant hyperthermia to get topical anesthetic eye drops during an eye exam? Specifically, proparacaine .5% or benoxinate .4%? My understanding was that this condition affects inhaled general anesthetics but not topical ones, but I am not certain. Thank you!

The drugs you are asking about are short-acting local anesthetics used to provide topical anesthesia for eye operations such as cataract surgery. They are very widely used and have an excellent safety profile.

Malignant Hyperthermia is a rare but serious syndrome that is related to certain anesthetic agents. Research and experience has shown that exposure to inhaled volatile anesthesia agents and the muscle relaxant succinylcholine are triggering agents. They are not used when a patient either has the syndrome or has a family history of the syndrome. Other anesthetic agents, including local anesthetics, are felt to be safe. You can  feel safe with proceeding with eye surgery using the medications you asked about.

You can find more detailed information at the American Society Of Anesthesiology website,, and at the the Malignant Hyperthermia Association of the United States website,

Thank you for this important question and I wish you the very best.


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Charles T Porter Jr MD


Questions in all fields of Anesthesiology except Pain Management.


I have been in the practice of Anesthesiology since 1981.

American Society of Anesthesiologists, International Anesthesia Research Society, Texas Society of Anesthesiologists, Texas Medical Association

Graduate of the Citadel and the Medical University of South Carolina. Completed Anesthesiology residency at the Naval Medical Center San Diego, California. Board certified in Anesthesiology and a Fellow of the American College of Anesthesiologists.

Awards and Honors
Alpha Omega Alpha National Medical Honor Society 1978, Outstanding Graduate Anesthesiology Resident Naval Medical Center San Diego California

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