BMJ Group Medical Reference
Terbinafine drugs belong to a group of drugs called allylamines. Allylamines are drugs that get rid of infections caused by fungi. Athlete's foot is caused by a fungus.
The only allylamine used as a tablet to treat athlete's foot is terbinafine. The brand name is Lamisil. You need a prescription from your doctor to get this medicine. Your doctor will usually only prescribe terbinafine tablets if treatments that you put on your skin haven't worked.
Terbinafine tablets are only usually prescribed if:
Your athlete's foot is very sore and painful
You've had athlete's foot for a long time
Your nails are also affected.
About 65 in 100 people who take terbinafine tablets for six weeks will be cured of their athlete's foot. 
About 1 in 5 people who take terbinafine tablets get some side effects. These are usually digestive problems, such as  
Terbinafine is no more likely to cause these problems than other tablets used to treat athlete's foot. 
Terbinafine tablets can cause other, rare side effects, such as skin rashes and loss of appetite.  Before you decide to take this drug, you should talk to your doctor about these side effects.
Diarrhoea is when you have loose, watery stools and you need to go to the toilet far more often than usual. Doctors say you have diarrhoea if you need to go to the toilet more than three times a day.
A fungus is an organism that is sometimes considered to be a type of plant. A fungus lives by feeding on other organisms. The mushrooms we eat in salads are fungi, but so are candida and cryptococcus, which can cause infections in people's bodies.
For more terms related to Athlete's foot
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