Take tadalafil exactly as directed. Take tadalafil at around the same time every day. The FDA has also approved tadalafil for treatment of both benign prostatic hypertrophy and erectile dysfunction where the two conditions co-exist. You should take tadalafil one time a day. Your doctor will probably tell you not to take tadalafil if you are taking street drugs containing nitrates.CIALIS for Use as Needed. Creatinine clearance 30 to 50 mL/min: A starting dose of 5 mg not more than once per day is recommended, and the maximum dose is 10 mg not more than once in every 48 hours. Creatinine clearance less than 30 mL/min or on hemodialysis: The maximum dose is 5 mg not more than once in every 72 hours [see .  · How GoodRx Works. Compare prices. Drug prices vary by pharmacy. Use GoodRx to find current prices and discounts. Get free coupons. GoodRx coupons can help you pay less than the cash price for your prescription. Show to your pharmacist. It’s easy. Just bring your free coupon to the pharmacy when picking up your prescription. You may be able to get a day supply of Cialis if approved by your insurance company. This could reduce your number of trips to the pharmacy and help .