Prostaglandin E(1)-based vasoactive cocktails in erectile dysfunction: how environmental conditions affect PGE(1) efficacy.
BACKGROUND
The chemical stability of prostaglandin E(1) (PGE(1)) in physiological solution has been studied in different environmental conditions. However, very little data exist regarding the PGE(1) stability and the consequent breakdown products in PGE(1)-based vasoactive cocktails under different environmental conditions.


OBJECTIVE
To evaluate the loss of the therapeutic efficacy of PGE(1) either alone or in combination with other vasoactive substances under different storage conditions.


METHODS
Utilizing high performance liquid chromatography the PGE(1) content was evaluated alone and in association with papaverine and papaverine plus phentolamine at temperatures of 2-8 and at 20 degrees C, and after 15, 30, 60, 90 and 120 days of storage using multivariate statistical analysis of variance.


RESULTS
We found that the time of storage significantly affects PGE(1) activity. Furthermore, both the storage temperature and cocktail composition had a significant effect on PGE(1) stability. The chromatographic studies did not disclose the presence of the principal degradation products of PGE(1) (PGA(1), PGB(1)). The presence of papaverine and temperature of 20 degrees C have the greatest effect on the degradation of PGE(1 )during the first 30 days of storage.


CONCLUSIONS
Temperature and time are prevalent factors determining the slow and progressive deterioration curve of PGE(1) after 30 days of storage. None of the environmental conditions evaluated was so drastic to determine the presence of PGA(1) and PGB(1).


CONCLUSIONS
For clinical use, one should note that PGE(1) maintains 50-80% of its efficacy for about 1 month even if stored at room temperature (20 degrees C) and/or combined with papaverine.
Bertaccini
A
A
Department of Urology, University of Bologna, Italy. bertacc@tin.it
Gotti
R
R
Soli
M
M
Carparelli
F
F
Ceccarelli
R
R
Cavrini
V
V
Martorana
G
G
D000527:Alprostadil / Q000493:pharmacokinetics* / Q000627:therapeutic use; D004355:Drug Stability; D004359:Drug Therapy, Combination; D007172:Erectile Dysfunction / Q000188:drug therapy; D006801:Humans; D008297:Male; D013696:Temperature; D014665:Vasodilator Agents / Q000493:pharmacokinetics* / Q000627:therapeutic use
D014665:Vasodilator Agents; D000527:Alprostadil