Section 12: Urological Disorders
Which of the following medications for erectile dysfunction is administered as a tablet which should be put on the tongue and allowed to dissolve?
The answer is D. Staxyn is an oral dispersible tablet formulation of vardenafil. It is considered convenient to use because it does not require that the patient swallow the tablet or take it with water. Instead, it dissolves quickly in the patient’s saliva when put on the tongue.
After taking vardenafil 10 mg, taken on demand on three separate occasions, the patient returns to the physician’s office to complain that the medication is not working. His erectile dysfunction has not responded to treatment. The most appropriate action that the physician should take at this time is:
A. Discontinue vardenafil and switch the patient to a vacuum erection device.
B. Switch the patient from on-demand vardenafil to daily vardenafil 10 mg.
C. Continue with vardenafil 10 mg on demand for a total of 7 to 8 doses and review the instructions for proper use.
D. Increase the vardenafil dose to 20 mg and instruct the patient to try this the next time.
E. Combine vardenafil 10 mg with intracavernosal alprostadil and instruct the patient to take both on demand.
The answer is C. A minimum clinical trial of a particular dosing regimen of a phosphodiesterase inhibitor is 7 to 8 doses. Therefore, the most prudent course is to allow the patient to have a minimal clinical trial with one dosing regimen before increasing the dose, switching to another phosphodiesterase type 5 inhibitor, or switching to another treatment for erectile dysfunction.
If sildenafil is taken with rifampin, the drug interaction may result in:
A. Decreased efficacy of sildenafil
C. Increased blood pressure
The answer is A. Sildenafil principally is metabolized to inactive metabolites by hepatic CYP3A4 enzymes. Therefore, rifampin, a CYP3A4 inducer would be expected to enhance sildenafil’s catabolism and decrease sildenafil’s efficacy.
Which one of the following statements about ...