Drew Barrymore -- Good Genes or Good Docs

It looks like Drew Barrymore has never been kissed by age!

Here’s an 18-year-old version of the actress channeling her inner Marilyn Monroe at the Billboard Music Awards (left) and 23 years later ... the Golden Globe winner -- who celebrated her 41st birthday earlier this week -- at a forum in New York City (right).

Aging ... so extraterrestrial.

The question is ...