Get emergency medical help if you have signs of an allergic reaction (hives, difficult breathing, swelling in your face or throat) or a severe skin reaction (fever, sore throat, burning in your eyes, skin pain, red or purple skin rash that spreads and causes blistering and peeling).
Seek medical treatment if you have a serious drug reaction that can affect many parts of your body. Symptoms may include: skin rash, fever, swollen glands, flu-like symptoms, muscle aches, severe weakness, unusual bruising, or yellowing of your skin or eyes. This reaction may occur several weeks after you began using terbinafine.
Some people taking terbinafine have developed severe liver damage leading to liver transplant or death. It is not clear whether terbinafine actually caused the liver damage in these patients. In most cases, the patient had a serious medical condition before taking terbinafine.
Call your doctor at once if you have symptoms of liver damage, such as nausea, upper stomach pain, vomiting, loss of appetite, tiredness, dark urine, clay-colored stools, or jaundice (yellowing of the skin or eyes). These events can occur whether or not you have ever had liver problems before.
Also call your doctor if you have:
changes in your sense of taste or smell;
depressed mood, sleep problems, lack of interest in daily activity, feeling anxious or restless;
pale skin, easy bruising, unusual bleeding (nose, mouth, vagina, or rectum), purple or red pinpoint spots under your skin;
swelling, rapid weight gain, little or no urinating;
blood in your urine or stools;
weight loss due to taste changes or loss of appetite; or
skin sores, butterfly-shaped skin rash on your cheeks and nose (worsens in sunlight).
Common side effects may include:
diarrhea, nausea, gas, stomach pain or upset;
rash;
headache;
abnormal liver function tests.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
 Terbinafine side effects (more detail)
