Tadalafil: Price, Dosage & Where to Buy

Tadalafil is a long-acting phosphodiesterase 5 (PDE5) inhibitor prescribed for the treatment of erectile dysfunction, the signs and symptoms of benign prostatic hyperplasia, or both conditions together. It requires a prescription in the United Kingdom. Generic tadalafil has been available since 22 May 2018.

Tadalafil is indicated for three main uses. First, it treats erectile dysfunction in men who have difficulty achieving or maintaining an erection suitable for sexual activity. Second, it treats the signs and symptoms of benign prostatic hyperplasia, a non-cancerous enlargement of the prostate gland that can cause urinary symptoms such as difficulty starting urination, weak stream, and frequent or urgent need to urinate.

Third, it treats both erectile dysfunction and benign prostatic hyperplasia when a man has both conditions at the same time. When tadalafil is used with finasteride to start treatment for benign prostatic hyperplasia, that combination is recommended for up to 26 weeks, because the added benefit of tadalafil decreases from 4 weeks until 26 weeks, and the benefit beyond 26 weeks is not known.

Tadalafil belongs to a class of medicines called phosphodiesterase 5 inhibitors. These medicines work by blocking an enzyme called phosphodiesterase type 5, which is found in the smooth muscle of blood vessels in the penis and prostate. When this enzyme is blocked, levels of a chemical messenger called cyclic guanosine monophosphate increase.

This leads to relaxation of smooth muscle and increased blood flow. In erectile dysfunction, this improved blood flow helps a man achieve and maintain an erection when sexually stimulated. In benign prostatic hyperplasia, relaxation of smooth muscle in the prostate and bladder can help improve urinary symptoms such as hesitancy, weak stream, and the need to urinate frequently or urgently.

Tadalafil is available as 2.5 mg, 5 mg, 10 mg, and 20 mg tablets, as well as a 20 mg/5 mL oral suspension. For erectile dysfunction used as needed, the usual starting dose is 10 mg prior to anticipated sexual activity. The label lists a possible increase to 20 mg or decrease to 5 mg based on individual response and tolerability.

The label states that tadalafil improves erectile function compared to placebo up to 36 hours following dosing, and the maximum recommended dosing frequency is once per day. For erectile dysfunction used once daily, the usual starting dose is 2.5 mg once daily without regard to timing of sexual activity, and the label lists a possible increase to 5 mg based on individual response. For benign prostatic hyperplasia, the label lists 5 mg once daily at approximately the same time every day.

For erectile dysfunction and benign prostatic hyperplasia together, the label lists 5 mg once daily. Tadalafil may be taken without regard to food. Dose adjustments are listed for people with kidney or liver impairment and for those taking certain other medicines.

For tadalafil used once daily, if a dose is missed it should generally be taken as soon as remembered, unless it is nearly time for the next scheduled dose. In that case, the missed dose should be skipped and the regular schedule resumed. Doses should not be doubled to make up for a missed dose.

For tadalafil used as needed before sexual activity, there is no daily schedule, so the concept of a missed dose does not apply. The label states that the maximum dosing frequency for as-needed use is once per day in most patients. Patients with questions about timing should speak with their doctor or pharmacist.

Tadalafil is not indicated for use in females. There are no data on the use of tadalafil in pregnant women. In animal reproduction studies, no adverse developmental effects were observed when tadalafil was given orally to pregnant rats or mice during organogenesis at exposures up to 11 times the maximum recommended human dose of 20 mg daily.

In a rat prenatal and postnatal development study, postnatal pup survival decreased following maternal exposure to tadalafil doses greater than 10 times the maximum recommended human dose based on drug exposure levels. Tadalafil and its metabolites cross the placenta, resulting in fetal exposure in rats.

There is no information on the presence of tadalafil or its metabolites in human milk. Tadalafil and its metabolites are present in the milk of lactating rats at concentrations approximately 2.4-fold greater than found in plasma.

The label states that tadalafil tablets should be stored at 20° to 25°C (68° to 77°F), which corresponds to controlled room temperature. The medicine should be kept in its original container to maintain quality. As with all medicines, tadalafil should be kept out of the reach of children.