The body takes longer to absorb it after a high-fat meal or alcohol. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. It’s available in 10 mg and 20 mg tablets. The FDA has also approved tadalafil for treatment of both benign prostatic hypertrophy and erectile dysfunction where the two conditions co-exist. Always discuss with your health care practitioner ALL of the medications you are taking prescription and over-the-counter that way, you can receive the best advice for your own situation. Levitra vardenafil : This medication is taken one hour before sex and can last up to 24 hours.A sildenafil (generic Viagra) membership starts at $20 monthly for six tablets of 30 mg. For $ each month, you’ll receive 34 sildenafil tablets of 45 mg each. Generic Viagra (sildenafil): $20 to $ per month. Generic Cialis (tadalafil): $20 to $ per month. Tadalafil is a medicine used to treat erectile dysfunction (ED, also called impotence) and problems with urination caused by an enlarged prostate (benign prostatic hypertrophy or BPH). It is sometimes known by its generic name tadalafil, and sometimes known by its trade name, Cialis. There are also other brands of this medicine available. Tadalafil (Cialis) is available both as brand-name and generic tablets. Common side effects of this medication include headache and indigestion. Tadalafil Missing: amazon.