Swallow the pill whole. Also, patients that are currently taking medicines with substances such as nitrates and guanylate cyclase stimulators should avoid Tadalafil to prevent unsafe drop or increase in blood pressure. Who should not take Cialis? However, because sexual stimulation is required to initiate the local penile release of nitric oxide, tadalafil’s inhibition of PDE5 will have no effect without sexual stimulation. You could get dizzy, faint or have a heart attack or stroke.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. The cost for Cialis oral tablet mg is around $ for a supply of 30 tablets, depending on the pharmacy you visit. Quoted prices are for cash-paying customers and are not valid . The most commonly reported side effects in patients treated with Cialis during the testing of the product were: headache. indigestion. back pain. muscle pain. flushing. stuffy nose. Patients who.