Viagro his medicine may be taken with or without food, but its onset of action may be delayed if it is taken with a meal high in fat. Unless your Viagro or pharmacist tells you otherwise, avoid drinking grapefruit juice while taking this medicine, as Viagro it may increase the level of this medicine in your blood and hence increase the risk of side effects. If your Viagro, consult a doctor immediately. Treatment of this condition should not be delayed more than 6 hours, as Viagro this can cause damage to the erectile tissue in the penis and erectile dysfunction.