What Is Tadalafil?

Treatment of erectile dysfunction is closely connected with Cialis, which active agent is tadalafil. This substance belongs to the class of selective PDE-5 inhibitors and has been showing high effectiveness in treating erectile dysfunction and benign prostatic hyperplasia for more than 10 years. Now tadalafil is used not only in brand Cialis, but also in its generic versions. Generic Cialis review shows that it is the same effective and reliable.

Mechanism of Action

The action of tadalafil is based on its ability to increase the amount of special type of cyclic guanosine monophosphate which results in better relaxation of smooth muscles in the target area. Thanks to it, the blood flow improves leading to stable and sufficient erection for performing a sexual intercourse. Tadalafil starts working only when sexual stimulation is present, as it is necessary for nitric oxide ejection, so erection appears only when it is needed.

Peculiarities of Use

There are tablets of different strength with a corresponding amount of tadalafil as the effect is based on personal sensitivity to the drug and state of the patient. The doses available are 2.5 mg, 5 mg, 10 mg and 20 mg.

The most common single dose of tadalafil is 10 mg. The maximum dose is 20 mg a day. Drug administration should not be more often than once per 24 hours. If a patient suffers from renal insufficiency, hepatic impairment or takes concomitant medicines, the dose should be decreased in accordance with the state of the patient.

The tablet should be taken orally with or without food as its metabolism doesn’t depend on this factor. It is absorbed into blood and metabolized by CYP3A4 which means the type of metabolism is hepatic. It is rather individual how fast the substance is absorbed – the maximum level of tadalafil in blood might be observed from 30 min after medicine administration up to 6 hours. However, the usual amount of time needed for full absorption is about 2 hours. Tadalafil is distributed by means of binding to proteins which transport it to the target tissues. Permanent level of tadalafil in blood in case of daily therapy is achieved in 5 days. In general, the effect might be observed up to 36 hours after single administration of a tablet.

Tadalafil is excreted mainly via feces, also urine takes part in the excretion process but in a less extent.


As for tadalafil contraindications, they include:

  • Allergy to tadalafil itself or any other inactive agent the tablets contain;
  • Nitrates therapy – in a combination with tadalafil they might result in excessive hypotension;
  • Administration of alfa-blockers.

It is necessary to tell your doctor about the following conditions before deciding on whether to take the medicine and choosing the dosage:

  • Heart diseases or other cardiovascular conditions;
  • Blood or bleeding disorders;
  • Liver or kidney diseases;
  • Stomach ulcer;
  • Retinitis pigmentosa;
  • Deformation of penis.

In some conditions sexual intercourses may be contraindicated at all, which means tadalafil should not be prescribed till the state of the patient improves.

In addition, it’s crucial to remember that tadalafil and alcohol, grapefruit or other medicines and remedies for erectile dysfunction treatment should not be combined as the action of tadalafil might diminish, or side effects may appear.

Side Effects

There are some typical Cialis side effects which don’t need to be cured and disappear as soon as your body gets used to the drug. They are:

  • Headache;
  • Diarrhea;
  • Muscle pain;
  • Sinus pain.

In case of the following side effects it’s necessary to seek for medical help:

  • Breathing problems;
  • Irregular heartbeat;
  • Pain in the chest;
  • Long-lasting painful erection (lasting longer than 4 hours);
  • Vision changes or loss;
  • Hearing changes or loss;
  • Seizure;
  • Lightheadedness;
  • Swelling in feet, ankles, hands.