Are there drug interactions?  I'm sure I have seen some meds that warn against grapefruit.

Is the pineapple juice semen myth is true?.

Yes it is true.

If you consume large amounts of pineapple juice, your sperm and sweat will taste much sweeter than normal, that is if you venture to find out of course.
Consuming large amounts of pineapple juice raises the acid levels in the body, in addition to the sugar levels.
The body will use only what it needs within the pineapple juice, and then much of it will be excreted as waste through sweating, urinating, and other normal bodily functions.

Believe it or not, many of the foods you eat will dramatically affect your smell, taste, etc. Like the old saying goes, you are what you eat.
One such negative example of this fact of life, is if you consume large volumes of milk, yogurt, or other dairy products, your sweat will take on a very sour smell, part of which has to do with it souring in the digestive system.

Other much more pleasant examples of this fact, are when you eat large amounts of fruits, such as kiwis, oranges, lemons, green apples, or berries, all of which will sweeten your smell. Just like cigarette smokers often cannot detect the foul odor their body emits, supposedly this is also the case with individual who eat meat, and then hang out around vegans.

Supposedly individuals who eat meat have a clearly distinguishable smell, however uncomfortable that fact is.

So get eating fruit guys.

Below is my dessert at the Mandalay buffet this past May.