XXXX inhibitors: are there differences?

@entity1 @entity323 @entity7856 @entity120 @entity9498 @entity1507 @entity7855 @entity6697
The introduction of oral agents for the treatment of @entity323 ( @entity323 ) has revolutionized the treatment of @entity1 with erection problems of all severities and etiologies. @entity7855 , available on the world market since 1998 was joined in 2003 by @entity9498 and @entity6697 as effective save and reliable oral agents. While these agents share the method of action in common and are all contraindicated with @entity1507 medications, these are differences among the three agents. @entity7855 has the longest @entity1 experience and the most robust data confirming its activity, safety and tolerability. It has recently been released for use in @entity120 as well as @entity323 . @entity6697 , the most biochemically potent of the molecules has also been demonstrated to be effective in @entity1 with severe @entity323 and in some @entity1 failing @entity7855 . @entity9498 is unique in its longer half life and is also tolerable, safe and effective in all severities and etiologies of @entity323 . Tadalafil is also unique in its inhibition of PDE 11, a characteristic of unknown but probably negligible importance. Newer data have also suggested that these agents may be helpful in the treatment of lower urinary tract symptoms. Since the introduction of @entity7855 in 1998, @entity323 has been effectively treated with oral medications. The recent addition of @entity6697 and tadalafil to the market has increased the number of phosphodiesterase type 5 inhibitors ( @entity7856 ) to three agents used throughout the world. Each of these agents has similar mechanism of action, but has distinct differences. All three drugs in this class have similar pharmacokinetic and pharmacodynamic profiles and each is effective for @entity1 with @entity323 of all ages, severities and etiologies. While there are clear pharmacokinetic and pharmacodynamic differences amongst these agents, clinical differences are somewhat more difficult to identify. Indeed the data of preference trials, head to head clinical trials, and selection trials are few. The differences in pharmacokinetics while having distinct advantages in marketing each drug may be difficult for clinicians and @entity1 to identify. With the lack of data and well done clinical trials, it is difficult for the clinician to differentiate amongst the three agents and to select a @entity7856 inhibitor for a specific @entity323 @entity1 or a specific agent to switch to if an initial @entity7856 agent is unsuccessful or poorly tolerated. This discussion summarizes some of the current data on @entity7856 inhibitors and their efficacy, safety, and use in other conditions.
