My gp has prescribed me fluoxetine for pmt - you take it 2 weeks before period due, then come off it when it starts, then start again 2 weeks before due again, and continue like that. i've used fluoxetine as AD before and i don't understand that normally it takes 2 weeks to kick in - so how can it work if you only ever take it for a fortnight at a time? Bit sceptical about it really...