Hi.. Thanks for the query.. Yes, it is right that certain medications can cause a bad taste in mouth and Terbinafine can also be considered one of them.. But as it is not 5 weeks that you have stopped taking the medication the effect of it must have completely weaned off from the body, therefore it does not appears to be the cause of bad taste and smell.. Other common causes of bad taste in mouth can be oral and dental Infections, acid reflux, post nasal drip, upper respiratory infections etc. So my suggestion is to consult an Oral Physician and get evaluated.. For now chew flavoured sugar free chewing gum. Gargle with flavoured Mouthwash to mast bad taste.. You should use a tongue scraper to clean your tongue.. Avoid too much intake of high aroma foods like onion and garlic especially in raw form.. Hope this helps.. Regards..