It's funny; I moved out before Viagra came to market, and didn't watch much any commercial TV. Of course, I was bombarded, like everyone else, with spam and other online advertisements for viagra.
But yeah, the first time I saw a viagra ad on television, I was visiting my parents, and I couldn't stop laughing. I mean, this was something advertised in spam, and thus something linked in my mind to dubious 'penis enlargement' pills, girls who "saw my profile online" and 419 scams. Not the sort of thing you expect to see on broadcast television. (I'm not casting aspersions on viagra the drug... just the marketing I had been exposed to associated it, in my mind, with dramatically... less legitimate products.)