The four main medicines taken by mouth for erectile dysfunction are: Avanafil Stendra. If you are taking tadalafil for erectile dysfunction on a regular schedule, take the missed dose as soon as you remember it. Oral medicines for ED usually work well and cause few side effects. They include dutasteride Avodart, Jalyn and finasteride Propecia, Proscar. Comparison with actions of other PDE5 inhibitors[ edit ] Sildenafil and vardenafil inhibit PDE6, an enzyme found in the eye, more than tadalafil. How should this medicine be used?Tadalafil (Cialis) is taken by mouth either as needed before sexual activity or once daily for erectile dysfunction (ED).It’s also taken once daily to treat symptoms from an enlarged prostate (benign prostatic hyperplasia, or BPH).Tadalafil (Cialis) is available both as brand-name and generic tablets. Common side effects of this medication include . Tadalafil – STADA T20 – 20 Milligramm. Tadalafil, sold under the brand name Cialis among others, is a medication used to treat erectile dysfunction, benign prostatic hyperplasia, and pulmonary arterial hypertension. It is taken by mouth. Onset is typically within half an hour and the duration is up to 36 hours. Common side effects include headache, muscle pain, . 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.