CIALIS and other erectile dysfunction treatments

The efficacy and safety of combining CIALIS with other PDE5 inhibitors or other treatments for erectile dysfunction have not been studied.

Patients should be informed not to use such combinations.

Lactose

시알리스 contains lactose. Patients with rare hereditary galactose intolerance, Lapp lactase deficiency, or glucose-galactose malabsorption syndrome should not take this medicine.

CIALIS Drug Interactions -

Interaction studies have been conducted with the 10 and/or 20 mg dose of tadalafil, as indicated below. With regard to the interaction studies where only the 10 mg dose was used, these do not make it possible to exclude the possibility of clinically relevant interactions at higher doses.

Effects of other substances on tadalafil

Cytochrome P450 inhibitors

Tadalafil is primarily metabolized by CYP3A4. In the presence of a selective inhibitor of CYP3A4, ketoconazole (200 mg daily), the exposure (AUC) to tadalafil (10 mg) is multiplied by 2 and the Cmax increased by 15% compared to the values ​​of AUC and C max observed with tadalafil alone. At a dose of 400 mg per day, ketoconazole multiplies the exposure (AUC) to tadalafil (20 mg) by 4 and increases the Cmax by 22%. Ritonavir, a protease inhibitor of CYP3A4, CYP2C9, CYP2C19, and CYP2D6 (200 mg twice daily), increases the exposure (AUC) of tadalafil (20 mg) by 2, with no change in Cmax. Although specific interactions have not been studied, other protease inhibitors, such as saquinavir, and other CYP3A4 inhibitors, such as erythromycin, clarithromycin, itraconazole, and grapefruit juice, should be co-administered.

administered with caution as they may increase tadalafil plasma concentrations (see section 4.4). The incidence of the undesirable effects mentioned under Undesirable effects could therefore be increased.

Carriers

The role of transporters (such as P-glycoprotein) in the distribution phase of tadalafil is not known. Thus, there is, therefore, a potential risk of drug interactions due to the inhibition of transporters.

Cytochrome P450 inducers

Rifampicin, an inducer of CYP3A4, reduces the AUC of tadalafil by 88% compared to the AUC determined for tadalafil alone (10 mg). This decrease may reduce the effectiveness of tadalafil; the value of this reduction is not known. A decrease in tadalafil plasma concentrations cannot be ruled out when combined with other CYP3A4 inducers, such as phenobarbital, phenytoin, and carbamazepine.

Effects of tadalafil on other drugs

Nitrates

Clinical studies have shown that tadalafil (5, 10, and 20 mg) increased the hypotensive effects of nitrates. Administration of 시알리스 to patients receiving nitrates in any form is therefore contraindicated (see section Contraindications). The results of a clinical study carried out on 150 patients who received daily doses of 20 mg of tadalafil for 7 days, and 0.4 mg of sublingual trinitrate at various times showed that this interaction lasted more than 24 hours and n was no longer detectable 48 hours after the last dose of tadalafil. Thus, in a patient taking CIALIS whatever the dose (2.5 mg - 20 mg), and in whom the administration of a nitrate derivative is deemed necessary for the vital prognosis, a minimum period of 48 hours after the last intake of 시알리스 must be respected, before administering a nitrated derivative. In this case, nitrates should only be administered under strict medical supervision including appropriate hemodynamic monitoring.