Levitra interactions are necessary to be noted. Uncontrolled use of the drug may lead to serious Canadian Levitra side effects.
- Levitra (Vardenafil) metabolism predominantly involves the liver enzyme cytochrome P450 (CYP), namely, isoform 3A4, as well as some isoforms CYP3A5 and CYP2C9. Inhibitors of these enzymes may reduce Vardenafil clearance;
- Cimetidine (400 mg, 2 times a day): an non-specific inhibitor of cytochrome P450 has no effect on the value of AUC and Cmax parameters of Vardenafil (20 mg) at their simultaneous use;
- Canadian Levitra is contraindicated for concomitant use with active moderate or potent inhibitors of CYP3A4, such as ketoconazole, itraconazole, ritonavir, indinavir, clarithromycin and erythromycin. The combined application of the drug with ketoconazole, itraconazole, ritonavir, indinavir and potential CYP3A4 inhibitors can cause a significant increase in Vardenafil concentration in plasma.
Nitrates, donators of nitric oxide
- Levitra (Vardenafil) 10 mg administration 1 hour prior to the intake of nitroglycerin (0.4 mg sublingual) does not enhance the hypotensive effect in healthy patients. Levitra dose of 20 mg 1-4 hours prior to the nitrate intake (0.4 mg sublingual) enhances Vardenafil hypotensive action, but if Vardenafil is taken 24 hours prior to natrates intake, there is no hypotensive effect of nitrates in taking in healthy middle-aged men;
- Nicorandil is a potassium channel activator and contains a nitro group in its structure. The presence of the nitro group in the composition of nicorandil causes high probability of interaction with Levitra (Vardenafil);
- However, there is no sufficient information on the potential hypotensive effects of Canadian Pharmacy Levitra (Vardenafil) if combined with nitrates. Therefore, this combination is contraindicated.
Minor Possible Levitra Interactions
- Levitra 20 mg does not alter the AUC and Cmax parameters of glibenclamide (glyburide 3.5 mg dose) in case of their joint administration. it’s also defined that the pharmacokinetics of Levitra is not changed when combined with glibenclamide. Pharmacokinetic and pharmacodynamic interactions (effect on px and coagulation factors II, VII, X) are not observed in the combined use of Vardenafil 20 mg with warfarin (25 mg). The concomitant use with warfarin does not alter the pharmacokinetics of Levitra from My Canadian Pharmacy;
- There is no significant pharmacokinetic interaction between Vardenafil and nifedipine (30 or 60 mg). Concurrent use of Vardenafil and nifedipine does not lead to significant pharmacodynamic interaction;
- It is known that alpha-blockers cause a reduction in blood pressure, especially postural hypotension and syncope, so the question of the interaction of alpha-blockers and Levitra for erectile dysfunction when used together was carefully studied;
- Evaluation of blood pressure and heart rate during 10 hours after administration of Levitra dose of 5 mg or 10 mg 4 hours after taking alfuzosin revealed no clinically significant further reduction in average maximum blood pressure, if compared to placebo. One patient had a reduction from baseline arterial pressure by 30 mm Hg. Art. after taking Levitra 5 mg. The other patient had a reduction by more than 30 mm Hg. Art. after taking Levitra 10 mg. Cases of arterial pressure decline in the standing position in this case has not been identified. There were reports of dizziness in two patients after administration of Levitra 5 mg, one patient – after taking Levitra 10 mg, and one – after placebo. Potential interactions were identified within maximum 4-hour interval between doses of Levitra and alfuzosin, so the compliance with the time interval between drug administration is required. No cases of syncope have been identified after the combined use of Levitra and tamsulosin or terazosin;
- Combined administration of Levitra and alpha-blockers is permissible only in the stable rates of blood pressure in patients taking alpha-blockers. In this case Levitra should be administered at a minimum recommended dose 5 mg. However, Canadian Pharmacy Levitra in the form of dispersible oral tablets 10 mg should not be administered as the initial dose in concurrent therapy with alpha-blockers;
- Levitra should not be taken at the same time with alpha-blockers, except alfuzosin and tamsulosin, which intake may coincide with Levitra formulation. It’s necessary to follow an interval between taking Levitra and other alpha-blockers. The concomitant administration of terazosin and Levitra it’s necessary to wait 6 hours between these drugs administration. The simultaneous use of digoxin (0.375 mg) and Levitra 20 mg within 14 days is not accompanied by their interaction;
- A single dose of antacid (hydroxide / aluminum magnesium hydroxide) doesn’t affect Levitra effects;
- Bioavailability of Levitra 20 mg is not disturbed when it is combined with the H2-antagonist ranitidine receptor (150 mg, 2 times a day);
- Levitra 10 mg and Levitra 20 mg does not affect the duration of bleeding when used as monotherapy in combination with acetylsalicylic acid at a low dose;
- Levitra 20 mg does cause the hypotensive effect of alcohol (0.5 g / kg), the pharmacokinetics of Levitra from Canada is not violated. However, it’s not recommended to combine Levitra and alcohol;
- Aspirin, ACE inhibitors, beta-blockers, diuretics and antidiabetic drugs (sulfonylureas and metformin), CYP3A4 inhibitors do not affect the pharmacokinetics of Levitra.