Bethanechol Side Effects

Bethanechol is a prescription medication used to treat conditions that cause your bladder not to empty fully. Despite its effectiveness, Bethanechol poses a risk for side effects in some patients.

Significance

• Side effects from bethanechol are most common when given as an injection into fatty tissue rather than taken orally as a capsule, according to RxList.

Types

• Side effects of bethanechol include malaise, abdominal cramps, nausea, vomiting, diarrhea, stomach growling, salivation, frequent urination, headaches, decreases in blood pressure, flushing, sweating, constricted pupils and excessive tear production.

Drug Interactions

• Bethanechol may increase risk of a severe spike in blood pressure when used with hypertension medication Trimetaphan, Drugs.com reports. Severe gastrointestinal side effects such as diarrhea, abdominal pain and vomiting are possible warning signs of this interaction.

Risks

• Some patients develop symptoms similar to an asthma attack while taking bethanechol. This is caused by constriction of the airway, according to RxList. Without quick treatment, these attacks pose a risk for respiratory arrest or death.

Considerations

• There is no evidence that bethanechol poses a risk to fetal development, but doctors rarely prescribe the drug to pregnant women. People with a history of asthma, epilepsy, intestinal blockage, low blood pressure, Parkinson's disease or hyperthyroidism should not take bethanechol because of potential side effects, the Mayo Clinic cautions.