Why do you get red eye when you smoke weed?

Question

I've been trying to think of the biological effect and I have no idea as to why red eye occurs. I'm looking for serious medical answers please!

Answer 1

It is a strong irritant.  The toxins cause inflammation in the tender parts of the body.  Grow up and stop that c**p.

Answer 2

Think it has something to do with sugar levels in your blood as well, thats why you get the munchies.

Answer 3

It relaxes the blood vessels in the body, they dilate letting more blood flow into them and they are very visible in the eye giving 'red eye'

Answer 4

The main psychoactive ingredient in Marijuana (Cannabis Sativa) is THC (delta-9-tetrahydrocannabinol). Its effects include an increases in pulse rate, blood pressure, and  heartbeat. Eyes become bloodshot and often  dry mouth and throat occurs, and a crave for sweets, often referred to as "munchies". The increase in blood pressure causes the "red eyes" (easily treated with 2 drops of "Visine"), and the sudden drop of sugar level in the blood causes the "munchies" (chocolate or ice cream will increase the sugar level in the blood and the munchies will go away...)

Answer 5

its to let others know that you have been smoking!!

Answer 6

The first 2 answers were correct, the rest are just ridiculous. It is preventable, though. Whenever I smoke, one drop of clear eyes in each eye, and BAM no more red eyes.

Answer 7

it effect the blood vesils in the back of the eye. some visine clears it right up

Answer 8

This is certainly a sign of (heavy) indulgence.

Cannabis widens blood vessels (vasodilation). The eyes contain blood vessels which widen when you are stoned; hence the blood within the vessels is more visible against the white of the eye causing red-eye.

When the vasodilator is metabolized (when it wears off), the blood vessels return to normal and the red eye disappears.

Cannabis induced red eye is not the same as the red eye caused by inflammation, allergy or injury

The increase in the heart rate is linked to this widening of the blood vessels. The heart beats faster because the pressure is lowered. This is an effort to restore the pressure to normal, part of what's meant by homeostasis. Everything in the body is linked and balanced.

Hope this helps :-) x