May make this condition worse. If you will be taking this medicine for pulmonary arterial hypertension, your doctor will want to check your progress at regular visits. Sildenafil usually should not be taken more than once every 24 hours. Patients taking concomitant inhibitors of CYP3A4 may benefit from initiation at the lower dosage. Do not keep outdated medicine or medicine no longer needed. Ask your pharmacist for a list of the ingredients. Dose-related visual disturbances occurred more frequently at toxic levels, while blood pressure changes showed a low correlation.Viagra is available in three strengths: 25 milligrams (mg), 50 mg, and mg. Note: Sex and gender exist on spectrums. Use of the term “male” in this article refers to sex assigned at birth. Sildenafil is available as oral tablets of 25 mg, 50 mg, and mg strength for erectile dysfunction (ED). Most patients receive a prescription for 50 mg of oral sildenafil, taken as needed approximately 1 hour before sexual activity. The dose can be titrated upward to a maximum of mg or down to 25 mg based on individual effectiveness . 1 day ago · Both Viagra and sildenafil are available in mg, mg, and mg doses. REX MD currently has a out of 5-star rating on Trustpilot as of November About 84% of the over 3, reviews.