Consider therapy modification Dapoxetine: May enhance the orthostatic hypotensive effect of Phosphodiesterase 5 Inhibitors. Itraconazole or ketoconazole anti-fungals. When the blood vessel muscle cells relax, this expands the vessel and increases blood flow; this effect is referred to as vasodilation. If you have any of the following conditions you should discuss with your regular doctor before taking tadalafil: Sickle cell anaemia an abnormality of red blood cells. Up until its exclusive license ended, only the original developer Lilly was permitted sell tadalafil legally in the UK.heart attack symptoms – chest pain or pressure, pain spreading to your jaw or shoulder, nausea, sweating. Common Cialis side effects may include: headache; flushing (warmth, redness, or tingly feeling); nausea, upset stomach; stuffy nose; or. muscle pain, back pain, pain in your arms, legs, or back. This is not a complete list of side effects. The usual dose of tadalafil is 10 mg, no more than once per day, taken orally at least 30 to 60 minutes before sexual activity. Its effect may last up to 36 hours. 1, 6 The dose can be increased. 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. [4] [5] [7] It is taken by mouth. [7] Onset is typically within half an hour and the duration is up to 36 hours.