People with heart conditions should never take ED medications without consulting a doctor. These include a heart attack, stroke or a serious heart rhythm disorder in the past six months. This is likely to lead to dramatic price reductions. Some people may also have ringing in their ears tinnitus or dizziness. You’ll also need to fill out a medical questionnaire with answers about your medical history, current medications, and lifestyle habits. This medication is taken with or without food an hour before sex.The usual recommended dose is 25 to mg 1 hour before sexual activity. The maximum dose is mg daily. The elderly (over 65 years of age) should start at 25 mg before sexual activity. Sildenafil is rapidly absorbed. Maximum observed plasma concentrations are reached within 30 to minutes (median 60 minutes) of oral dosing . Medications Prescribed: Viagra, Cialis, Cialis Daily, Levitra, tadalafil, sildenafil, vardenafil. Generic offered: Yes. Why We Chose It. The simple combination of Rex MD’s online platform, its helpful customer service, and the abundance of ED treatment options make it a one-stop shop for all your sexual health needs. Typical dosing for Sildenafil (Viagra) The typical dose is to take 50 mg of sildenafil (Viagra) by mouth, about 1 hour before sex, as needed. The maximum recommended dose is mg. Don’t take sildenafil (Viagra) more than once daily (at any dose). Written by Brian Leonard, PharmD, BCACP, BCGP.