Betahistine hydrochloride is a medication indicated for the treatment of Meniere's syndrome, which often results in vertigo, nausea, vomiting, hearing loss and inner ear inflammation. Betahistine hydrochloride works by altering the levels of histamine-1 and histamine-3 in the body, which can help dilate blood vessels in the brain that mediate some of the symptoms of Meniere's syndrome. Betahistine hydrochloride has been studied extensively in clinical trials and post-marketing research and has proven generally safe and effective, but it may also cause several side effects ranging from mild to serious.
Hypersensitivity and Allergic Reactions
Patients taking betahistine hydrochloride may experience several hypersensitivity and allergic reactions. In the November 2006 issue of "Drug Safety," Dr. Sabine Jeck-Thole and Dr. Wolfgang Wagner reported that betahistine hydrochloride may cause several allergic and skin-related side effects. These include rash in several areas of the body; itching and hives; and swelling of the face, tongue and mouth. Other hypersensitivity reactions reported include tingling, numbness, burning sensations, shortness of breath and labored breathing. The study authors suggest that hypersensitivity reactions may be a direct result of betahistine's role in increasing histamine levels throughout the body. Hypersensitivity reactions quickly subside after betahistine has been discontinued.
Digestive Side Effects
Betahistine may also cause several digestive-related side effects. The package insert for Serc, a trade name for betahistine, states that patients may experience several gastrointestinal side effects. These may include nausea, upset stomach, vomiting, diarrhea and stomach cramping. These symptoms are usually not serious and subside in between doses. Patients experiencing chronic digestive problems may lower their dose to the minimum effective range and by taking betahistine with meals. Additional digestive problems may require that patients consult their physician in order to possibly find a suitable alternative.
Other Side Effects
Patients taking betahistine may experience several other side effects ranging from mild to serious. The package insert for Serc states that patients may experience nervous system side effects, including convulsions, daytime sleepiness, confusion and hallucinations. Some nervous system events may also partly be attributable to the underlying condition rather than the medication used to treat it. Other side effects listed in the package insert include low blood pressure and heart rhythm irregularities. The study by Jeck-Thole and Wagner also reports that patients may experience headache and liver problems, including increased liver enzymes and bile flow disturbances. Any side effects that persist or outweigh the relief of symptoms of the original condition may warrant that the patient consult their physician to adjust or change the medication.