Can my patients take tadalafil with alpha-blockers?

Alpha-blockers are commonly used in the  treatment of symptoms of benign prostatic  hyperplasia (BPH) and some are indicated for  hypertension. In the USA, tadalafil may be  prescribed with tamsulosin 0.4 mg (Flomax1)  Supplement  Vol. 2, No. 1, pp. 141–157, March 2005 153  daily, but is contraindicated with other alphablockers  (e.g., doxazosin (Cardura1), terazosin  (Hytrin1), prazosin (MinipressTM), and alfuzosin  hydrochloride (UroXatral1)).  Tamsulosin: Tamsulosin is a selective  alpha[1A]-adrenergic blocker commonly used  to treat lower urinary tract symptoms (LUTS)  and BPH symptoms. No significant blood-pressure  lowering effect was seen in a study testing  the interaction of tadalafil with tamsulosin 0.4  mg administered once-daily [59].  Doxazosin: In the USA, tadalafil is contraindicated  with doxazosin and other alpha-adrenergic  blockers (with the exception of  tamsulosin 0.4 mg once daily). When tadalafil  20 mg was administered to healthy subjects  taking doxazosin 8 mg daily, there was an  augmentation of the blood-pressure lowering  effect of doxazosin, and the number of  subjects with potentially clinically significant  standing blood pressure decreases was greater  for the combination of doxazosin and tadalafil  compared to the combination of doxazosin  and placebo [60]. There were no cases of syncope.  Variation in label language: The contraindication  with alpha-blockers is specific to the US  label. Information regarding the concomitant  use of alpha-blockers depends upon the country  and the associated label for which such use  is being considered. Please refer to the package  insert pertaining to your locale when advising  whether the concomitant use of tadalafil and  alpha-blockers is contraindicated, ‘‘discouraged,’’  ‘‘not recommended,’’ or ‘‘used with  caution.’’