You take one 2. Shipping: Discreet, fast shipping is a must. More serious side effects may include a drop in blood pressure or an erection that lasts longer than four hours. If you have sex on a less regular basis, or your ED comes and goes, Cialis may be a better option. However, the dosage can range from 25— mg. Thanks to the higher dose, as-needed Cialis starts working quickly and typically reaches its peak concentration within two hours. These PDE5 inhibitors may cause headache, flushing, drop in blood pressure, or other adverse effects.Key takeaways: Telemedicine helps you access healthcare easier — through online access. It lets you have a medical visit and get a prescription online without having to see a provider in person. With telemedicine, an online provider can review your medical history, check your symptoms, and treat you. So getting a prescription is easier. 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 . CIALIS for once daily use is a lower dose you take every day. • Do not take CIALIS more than one time each day. • Take one CIALIS tablet every day at about the same time of day. You may attempt sexual activity at any time between doses. • If you miss a dose, you may take it when you remember but do not take more than one dose per day.