THC tolerance – What is it, and why does it build up?

From the first time you smoke cannabis, your brain develops a tolerance to THC (tetrahydrocannabinol) - the psychoactive chemical in cannabis that passes the blood-brain barrier and makes you feel “high”.

Repeated cannabis consumption diminishes the effect of THC on your brain, meaning you have to smoke more cannabis and more potent strains to get high.  

THC tolerance is why cannabis consumption can quickly spiral out of control – you can quickly need more and more of it to get your buzz.  

Over time, you can become so tolerant to THC that you no longer get high but crave it to feel normal. This creates a dependency that is hard to shake, and most experts would call you addicted (but we won’t use that word here).

What is tolerance?

THC Tolerance is when your brain is used to cannabis, so you experience weakened effects and need to smoke more to achieve the high you want.

Tolerance is problematic because it promotes cannabis misuse and binging. Unfortunately, this is a downward spiral and can be challenging to break.

Why does tolerance build up?

Tolerance to THC occurs when the brain takes action to minimise the effects of THC on CB1 receptors. CB1 receptors are cannabinoid receptors that, when activated, stimulate the brain, inhibiting and enhancing specific chemical processes.

Repeated cannabis consumption puts the brain into maintenance mode, where it protects the CB1 receptors from THC. Smoking more cannabis and more potent strains breaks the barrier, but that barrier always comes back stronger.

The effects of THC weaken, and you need more of it to achieve the high – this is tolerance, and unfortunately, it is systematic to most stimulants.

How long before I become THC tolerant?

If you smoke cannabis, you already have some THC tolerance – tolerance starts building the moment you inhale your first toke.

However, if you smoke recreationally, you are unlikely to build up enough tolerance not to get high when you smoke the average joint.

Complete tolerance is rare because anyone can still get high with enough THC in their system. Still, it usually takes three to six months of high to mid-frequency smoking (one to three spliffs/joints/blunts per day) to build up so much tolerance that you need a lot more cannabis to achieve the high you want.

A detox will break your tolerance cycle!

We have good news if you’re willing to go on a detox – tolerance to THC diminishes over time, and a thirty-day detox promises good results.

This study of cannabis users found that the brain recovers relatively quickly during cannabis abstinence. Results show that after four weeks of abstinence from cannabis, CB1 receptors returned to normal levels, demonstrating down-regulation.

Compared to alcohol and hard drugs, cannabis is less damaging to the brain, but you should still proceed with caution when using it.

Of course, after a thirty-day detox, you might not want to pick up another joint – and that’s fine. You can still use CBD products for some of the positive effects of cannabis without THC.