It’s also sometimes used to treat pulmonary hypertension high blood pressure in the blood vessels that supply the lungs. The most common side effects are headaches, feeling sick, indigestion and facial flushes. However, it stays in your body for up to 36 hours and can be taken every 24 hours, so it can work for you constantly. Talk with your healthcare provider about your sex life and desired use. Viagra vs. Cialis can be taken daily, providing constant treatment for ED for people who have sex frequently. Phosphodiesterase type 5 PDE5 inhibitors.Save £ Was £ 4 UNI | £ per 1UNI. Save 10 percent on Cialis Together 10mg Tablets Tadalafil 4 Tablets. Free next day delivery on selected medicines when you use code HEALTHFNDD, order by 8pm – online only. Helps you get and maintain an erection when you need it. Effective up to 36 hours. Cialis comes in several different strengths, including: milligrams (mg) 5 mg. 10 mg. 20 mg. The cost for these different strengths depends on whether you have insurance, your individual plan. Cialis is not right for everyone. Only your healthcare provider and you can decide if Cialis is right for you. Ask your healthcare provider if your heart is healthy enough for you to have sexual activity. You should not take Cialis if your healthcare provider has told you not to have sexual activity because of your health problems.