When practicing Viparita Karana, start out slowly – no more than 5 to 10 minutes at a time until your body adjusts to being in this position. Build up to 15 minutes and you’re good to go!
As with any asana, there are some precautions. Do not try to climb higher up the wall with your feet! If you have a neck, hip, or back injury, you should avoid doing this pose. People with glaucoma or history of cardiac/stroke issues may want to avoid this asana because it will increase pressure around the head and heart.
From: tiphero.com
Amazingremedy.com
Yoga With Adriene (Youtube)
