Movie where an alien slug attaches to people's backs, makes their tongues long, and makes them kill other people when kissing

Question

I'm looking for a movie I saw on TV once (when I shouldn't have lol) about 23 years ago. There was this slug alien or something that attached to people's backs and made their tongues long and killed people when they kissed them. This old lady picks up the slug and cradles it like a baby in her arms and coo's to it. I remember a chick kissing a guy on a subway or train and the tongue went right through his head.. this movie has been bugging me since then.

Answer 1

It is perhaps Brain Damage (1988). Plot summary -

a young man who becomes acquainted with a talking parasite known as Aylmer (voiced by John Zacherle) that injects him with an addictive fluid that causes euphoric hallucinations; in return, Aylmer demands that Brian allow him to feed on the brains of other humans

The subway kissing scene is the host and his girlfriend , and the kiss killed the girl. The old lady is the previous owner of the creature who jealously want the creature back as she suffered severe drawback due to the creature moving to another host.

The scene you are referring to is maybe this - Subway scene

Brain Damage Wikipedia for further plot summary

Answer 2

I believe it's 1994's "The Puppet Masters".

"The Earth is invaded by stingray-shaped alien "slugs" that ride on people's backs and control their minds.".

Strange aliens land in the Midwest, taking over people's minds in order to spread their dominion. Sam Nivens and Andrew Nivens, aided by Mary Sefton, are part of a government agency who must stop the the aliens before the aliens get to them.

The Puppet Masters Imdb

For further detailed plot summary - The Puppet Masters Wikipedia

Enjoy!