When you are my age no hiding the fact of the necessity!!

a couple of gals remarked that I seem to be a bit more, ahem, virile, shall we say, lately, and I gave attribution where it was due.

 
Mostly I am interested in seeing if gals say anything or not, just for sake of curiosity.

It's not really any of their business.   I don't ask if their hooters are enhanced.

At my advanced age I just presume they're presuming.  

The only time I'd feel a need to tell a lady what I'd ingested is if she was missing one of her piercings after our session.

I only take a small dose of viagra (20 - 40 mg) when I’ve had a few drinks.  I’m sure I’ll need it more in 5 or 10 years.  

No, I’ve never seen any reason why that would come up in conversation, except once.  One time I was in Vegas and got so drunk I forgot to take it.  The duo showed up and they were so hot, it didn’t matter, I was able to perform just fine.

After the session, I realized I was pretty drunk and hadn’t taken any V and I told them that was the first time in years that I was able to perform, while drunk, without any ‘help.’

They definitely took it as a compliment (as was intended).

So to answer your question, no I don’t disclose when I do take it, but I did once mention that I didn’t take it!