The usual dose of Levitra is 10 milligrams with a maximum dose of 20 milligrams in a period of 24 hours. 10 milligrams of this drug must be taken as needed approximately 25 to 60 minutes before sexual activity. This drug may be increased to a maximum dose of 20 milligrams as well as be decreased to 5 milligrams based on its efficacy and a person’s tolerability. A starting dose of 5 milligrams per day is used necessarily and should be considered by male patients who are aged 65 years old and older.
The recommended frequency for this medication is 10 milligrams in 24 hours. Its maximum recommended dose frequency is once daily. When Levitra is taken one hour before sexual intercourse, it is effective in producing an erection which can last about one to two hours. However, in clinical trials, Levitra is shown to be effective when taken up to four to five hours before sexual activity. Nevertheless, there must be sexual stimulation required for a natural response to treatment in order to produce an erection. The peak action of Levitra occurs in 30 to 120 minutes.
For those male patients who have mild hepatic impairment, no dose adjustment is needed. Since the clearance of Levitra is reduced in male patients who have moderate hepatic impairment, the recommended starting dose is 5 milligrams, which may subsequently be increased to a recommended maximum dose of 10 milligrams, based on the patient’s tolerability and its efficacy.
For those male patients who have impaired renal function, there is no dose adjustments needed for those with mild creatinine clearance of less than 50 to 80 milliliters per minute as well as for those with moderate creatinine clearance of less than 30 to 50 milliliters per minute. For those male patients who have severe renal impairment with a creatinine clearance of less than 30 milliliters per minute, the recommended starting dose should be considered at 5 milligrams.
For male patients who have been concomitantly using alpha-blockers, they should take note that the use of Levitra has vasodilatory effects similar to that of alpha-blockers. The use of this drug with similar drugs could lead to increased incidences of hypotension in some patients.
For male patients who have been concomitantly using potent CYP3A4 inhibitors such as ketoconazole, itraconazole, erythromycin, clarithromycin, indinavir and ritonavir, dose adjustments are required for taking Levitra film-coated tablets. The maximum dose for Levitra of 5 milligrams film-coated tablets should not be increased when used concomitantly or in combination with the CYP or cytochrome P-450 3A4 inhibitors such as clarithromycin or erythromycin. Same maximum dose must be considered when used in combination with the potent CYP or cytochrome P-450 3A4 inhibitors such as ketoconazole or itraconazole. One should take note that Levitra should not be taken with dosages of more than 200 milligrams of ketoconazole or itraconazole. The concomitant use of Levitra in combination with HIV protease inhibitors such as ritonavir or indinavir are contraindicated because they are very potent inhibitors of CYP or cytochome P-450 3A4.