Cannabis can dehydrate. Drink more water than you do when you are not smoking.

Stress can cause skin problems, too. Try thinking about stress, physical or mental, that might be in the back of your mind (or squarely in front of it, for that matter). Resolve those.
How to Make the Time for Your Personal Goals | Zen Habits

Failing resolving your stress, there is an excellent supplement called Relora, which has helped me a lot, and also St. John's Wort for depression. Also: Relora can help you lose abdominal weight (the unhealthy kind).
Details about Stress-Related Appetite Control and Relaxation with Relora
Hypericum (St. Johns Wort) and Depression

Try using virgin coconut oil as a moisturizer. It's excellent.
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