Siva, I wonder if it might be better to use a liquid in which tadalafil does NOT dissolve. As I see it, the major questions are: preventing things from growing in the suspension, and preventing the compound itself from degrading - either from oxidation or from reaction with something in the liquid.
And it would be my guess that a compound that’s reactive with other things might be even more reactive in solution. Does that make any sense?
Anyway, thanks to a local compounding pharmacy, I now have 60 ml of Ora-Plus. And I already had a bottle of propylene glycol. And, amazingly enough, I have plenty of vodka. :-) So I have an embarrassment of options.
I don’t know how "preserved" PG is. Ora-Plus of course is preserved, but is mostly water. It’s just not clear to me which would be best, or whether it would make sense to use a combination of both.
The 2 gm of powder would last me almost a year, so whatever liquid I use needs to be anti-microbial and chemically inert to tadalafil for a long time. It would be easiest to mix the whole 2 gm with liquid to start with, so I don’t have to divide it up, and then draw off maybe 20 ml at a time from which the actual dose could be drawn.
I’m kinda tempted to mix the 2 gm of powder with the 60 ml of Ora-Plus, which would give me 33.33 mg per ml, which works fine for me - it would be .6 ml per 20 mg dose, but I just don’t have a feel for whether something in the Ora-Plus might be reactive with tadalafil.
Here’s a link to a .pdf showing the ingredients in Ora-Plus.
http://www.padd ocklabs.com/for … sds/oraplus.pdf