LOGLINE:
I troubled teen concocts a psychedelic brew to help his dementia stricken grandfather, the only one who can give him the advice and guidance he so badly needs.

SYNOPSIS:
Henry lives with his single mother, Selena, and regularly cuts class to hang out with the wrong crowd.  She despairs of his behavior but is way too busy working to make ends meet to give him the attention he needs.  
Things becomes increasingly strained when Selena’s mother passes away and they’re forced to look after her ailing, dementia stricken father, Thomas.
At first Henry’s deeply resentful at looking after the old man, but as he learns more about Thomas, an old style, tough guy Marine who’s seen service all over the world, he begins to respect and admire him.  With his own life heading off the tracks, Henry needs some paternal guidance. Unfortunately, Thomas’s condition is too far advanced for any real bonding to take place.
Hearing about psychedelics from his drop out friends, Henry manages to obtain some magic mushrooms and uses them to concoct a medicinal tea for his grandfather. The results prove amazing, restoring the old man, for a very short time at least, to an approximation of his former self and providing Henry with the father figure he’s always yearned for.
Realizing his time is very, very short indeed and also that Henry’s heading down the path of self-destruction, Thomas resolves to use the brief moments of awakening to teach his wayward grandson his philosophy on life; how to be a man, take responsibility and live a good life.
The only question is, is there enough time to straighten out this ‘punk kid?’

I wasn't sure if I was allowed or not to post the synopsis here.
If I am not apologies, but any feedback on the logline would be very much appreciated.

I already have a 20 page short version of this written and me and a writing partner are considering turning this into a feature.

Hi James

I am going just off the logline, I haven't read the synopsis.

Feels like it is missing a few basic elements - What's the conflict in the story? what/who is the antagonist? What's at stake?

Yeah, we need to know what’s at stake. What kind of guidance? Is it life threatening? Need to know.

Thank you for the comments,. I think it is somewhat better now:

A troubled teen concocts a psychedelic brew to treat his dementia-stricken grandfather, the only one he feels might help him as his own life starts to come crashing down around him.