A guy goes to the pharmacist and says: "Listen, these two girls are coming over this weekend, and they are hot, very hot. Would you have something to get me going all night? It's going to be a hell of a party." The pharmacist goes in the back room, comes back with an old dusty bottle and tells him: "This stuff is potent: drink only one ounce of it, and I guarantee that you will be doing the wild thing all night. Let me know how it goes."
The weekend goes by and on Monday morning the pharmacist finds the same guy waiting for him outside the store. The pharmacist asks: "What are you doing here so early? And how was your weekend?" The guy replies: "Quick, I need Ben-Gay for the pain." The pharmacist, knowing what the guy had been doing all weekend, says: "Are you crazy, you can't put Ben-Gay down there. The skin is way too sensitive." The guy says: "No, no, It's not for that, it's for my arm." The pharmacist asks": "What?? What happened?" Guy replies, "Well...I drank the whole bottle of your potion." The pharmacist: "Oh my god, and then what?"
"The girls never showed up!"