This is a very informative article that I am sure many have questions about. I hope it helps. Though it does suggest Yoga to relax at the end, I do not suggest Yoga because of it’s attachment to an entirely other religion. Stretching would be fine.

Q. Pot smoking is legal in my state. I know pot is a bridge drug to other worse drugs. But I was wondering if occasionally smoking it is okay. My parish priest says there’s nothing wrong with it, so long as I don’t get dependent. What do you think? Thanks, Rahl.

A. I think your priest’s advice is misguided. The simple answer to the title question is: Although it is sometimes morally licit to smoke pot for purposes of healing, it is never licit to smoke it to get high?

“Brain Altering Substances” (BAS)
Medicine uses the term “therapeutic” to refer to something related to facilitating good physical or psychological functioning. Using BAS for therapeutic reasons is using them to obtain real human goods. But most BAS also have harmful effects, which mustn’t be the reason we choose them. In the words of moral theology, we mustn’t intend those effects as ends or means.
We all use BAS sometimes for therapeutic reasons, and many of us use them daily. We drink a cup of coffee or cola for an energy boost; we have a glass of wine to calm feelings of stress after a long day at work; we take antidepressants to ameliorate blue mood, or melatonin or Ambien to help quiet the sleep centers in our brain; we take analgesics to assist with back pain; and occasionally we take very powerful narcotics such as morphine to help relieve severe pain. Each of these can be done quite innocently, as each can be a way of realizing genuine human goods.
Marijuana is a BAS, which too, doctors tell us, can have therapeutic effects. Physicians sometimes prescribe it to…

http://www.ncregister.com/blog/christianbrugger/is-it-morally-licit-to-smoke-pot