What Are the Most Common Terbinafine Side Effects?

Terbinafine is an oral medication used to treat fungal infections of the toenails and fingernails. This medication is typically taken daily for six to 12 weeks. Terbinafine side effects exist, but a doctor is only likely to prescribe terbinafine if he or she feels the benefits outweigh the risks to a particular patient. Common terbinafine side effects include but are not limited to stomach issues, hives and changes in a patient's taste buds.

Among the more common terbinafine side effects are stomach issues. This strong medication can cause a patient to have stomach pain or diarrhea. Patients who feel they are experiencing chronic diarrhea should contact their doctors to see if it is safe to take an over-the counter anti-diarrhea medication or antacid. Men and women who have upset stomachs as a result of this medication also may experience vomiting. If a patient's quality of life is being affected by the vomiting, then he or she should set up a doctor's appointment.

Other typical terbinafine side effects include hives, itching and rashes. A patient should not stop taking his or her medication abruptly because of these side effects. Instead, a person experiencing any of these side effects should call his or her doctor to see if a cream or antihistamine medication can be prescribed to combat the side effects. Throat closing or trouble breathing combined with these side effects can be the sign of a serious allergic reaction, however, and patients with breathing issues should go immediately to an emergency room.

Loss of the ability to taste things or changes in a person's taste buds also are common terbinafine side effects. This medication can cause some people to taste metal in their mouths after eating. Other people may experience bitterness while eating certain foods that never tasted bitter before starting the medication. Some patients deal with this sensation by drinking tart beverages, rinsing their mouths often or adding strong spices to food. This side effect is typically more annoying than dangerous.

People need to let doctors know their full health history before they begin taking terbinafine. Patients with liver issues may not be good candidates for this medication. Individuals also should disclose their full current medication list to their doctors. Withholding information from a doctor about health history can cause a patient to experience some of the more serious and rare terbinafine side effects, including infection, sore throat, dark urine, chills and fever.