How long does loceryl take to work dapoxetine belongs to a class of selective serotonin reuptake inhibitors (SSRIs). This short-acting inhibitor is used to treat premature ejaculation in men. Take Dapoxetine by mouth with a glass of water, with or without food. Avoid cutting, crushing or chewing this medicine. Do not take the medicine more often than it is prescribed. Do not give up taking it except on the advice of your doctor. It may need time for the medicine to help. Consult your doctor concerning the proper dose for you.