Stop period pill it is taken by mouth with a glass of water approximately 0,5-1 hour before sexual activity. Fildena should not be taken more than once a day. A serious allergic reaction to this drug is very rare, but seek immediate medical help if it occurs. If you think you have used too much of this medicine seek emergency medical attention right away. The symptoms of overdose usually include chest pain, nausea, irregular heartbeat, and feeling light-headed or fainting.