Those who don’t feel comfortable discussing ED with an in-person provider or lack time to visit a doctor’s office may find online ED prescriptions beneficial. Combined use could lead to additional lowering of blood pressure, possibly to unsafe levels. When will Cialis be available to pharmacies? Always discuss with your health care practitioner ALL of the medications you are taking prescription and over-the-counter that way, you can receive the best advice for your own situation. People taking nitrates like nitroglycerin Nitrostat or isosorbide mononitrate Imdur should not take PDE5 inhibitors, as doing so could result in a dangerous drop in blood pressure.$ medication_outlined Availability Available See GoodRx coupons warning Are you looking for information on Adcirca (tadalafil) instead? What is Tadalafil . Cialis lasts up to 36 hours in the body, while Viagra lasts 4–6 hours in the body. Both are taken 30 minutes before sex. Cialis can cause limb pain, while Viagra can cause vision change, rash. MNT ‘s review. Lemonaid sells Cialis in these forms: Cialis: available in doses of 5, 10, and 20 mg, starting at $65 per tablet. Daily Cialis: 5 mg tablet with pricing starting from $50 per tablet.