Do I need a prescription for Tadalafil? In some cases, online ED providers accept health insurance. Reading about what’s good for you is even better. During the pandemic, rules prohibiting providers from prescribing these types of drugs without seeing a patient in person were waived. Remember that expediting will cost extra.Cialis doesn’t work right away. For the as-needed dose, plan to take Cialis at least 30 minutes before sexual activity, but bear in mind it may take as long as 2 hours to take effect. TADALAFIL/Cialis (tah DA la fil) treats erectile dysfunction (ED). It works by increasing blood flow to the penis, which helps to maintain an erection. based on the most recent information available and may change based on when you actually fill your prescription at the pharmacy. DISCOUNT ONLY – NOT INSURANCE. Discounts are available. Cialis Dosage. For the treatment of erectile dysfunction: On-demand dosing: The usual recommended dose is 20 mg taken as needed, at least 30 minutes before sexual activity. Cialis (Tadalafil) has been shown to be effective within 30 minutes of taking the tablet, and last up to 36 hours later.