Overdosing often causes side effects, for first time patients it’s recommended that only 50% (half a tablet) should be considered. The most common side effects are headache, flushing, heartburn, stomach upset, nasal stuffiness, light-headedness, dizziness or diarrhoea. A serious allergic reaction to this drug is very rare, but seek immediate medical help if it occurs. Many people who use this medicine do not have serious side effects. In case you notice any side effects not listed above, contact your doctor or pharmacist.