Weed and Birth Control: Do Cannabis and the Pill Interact?

Is there a known interaction between cannabis and hormonal birth control? There's no evidence that THC makes the pill less effective, but CBD may change how the liver processes estrogen-based contraceptives, and THC plus estrogen can both nudge blood pressure up. It's a topic getting more attention from doctors and from people who use both.

Hormonal birth control, like the pill, the patch and the ring, is widely used to prevent pregnancy by regulating hormone levels in the body, and cannabis use raises fair questions about how it might affect how well and how safely these methods work.

Here's a look at the evidence so far, the possible interactions between cannabis and hormonal birth control, and what they mean for your reproductive and sexual health.

Can cannabis affect the hormone levels birth control relies on?

Birth control is common among women in the United States, with roughly 65% using some form of it. Given how complex marijuana is, with more than 120 active compounds, some of them could interact with the effects of contraceptives, especially hormonal ones.

That said, neither the Centers for Disease Control and Prevention (CDC) nor the Food and Drug Administration (FDA) considers marijuana use a reason not to use contraceptives, no matter how it's consumed.

There's no evidence that smoking weed while on birth control makes the pill less effective. But some of THC's own side effects, like nausea or anxiety, could make the hormonal side effects of birth control pills, intrauterine devices (IUDs), patches, rings or implants feel worse.

CBD and birth control: what happens?

CBD, another cannabinoid in marijuana, is a different case: it could affect how the liver metabolizes certain drugs, including some types of hormonal birth control.

The evidence is limited, but there are signs that CBD may interfere with contraceptives that contain estrogen, while it doesn't seem to affect progestin-only ones. That could make progestin-based birth control a safer bet for people who want to use CBD and contraception at the same time, though more research is needed to confirm it.

Weed and birth control: possible risks and side effects

THC and some estrogen-based contraceptives can both raise blood pressure, which could increase the risk of heart complications when they're combined. If you have a history of heart problems or high blood pressure, talk to a doctor before mixing THC with hormonal birth control.

Birth control itself is generally safe, but it does carry some potential risks, including:

1. Blood clots
2. Heart attack
3. Stroke
4. Liver tumors

More broadly, the endocannabinoid system (ECS) has been shown to play a role in reproductive health and fertility, including egg production and embryo development. More research is needed to understand how THC might affect fertility when combined with contraceptives.

If you're pregnant or trying to conceive, current research suggests steering clear of cannabis, since it can affect pregnancy. Breastfeeding parents should also skip marijuana products, because THC can pass into breast milk and may harm the baby's health.

How CBD interacts with hormonal contraceptives

The interaction between CBD and estrogen could play out in different ways, from making birth control less effective to changing how your body metabolizes cannabis, which may lead to drowsiness and breakthrough bleeding (spotting between periods).

If you use CBD regularly, progestin-only methods, like the Depo-Provera (DMPA) shot, could be the more effective option.

Keep in mind that tobacco can complicate things further for anyone combining CBD and hormonal birth control. Smoking cigarettes while on hormonal contraception is a well-known risk factor that significantly raises the odds of serious health problems, like blood clots.

Birth control and weed: how much does the interaction really matter?

Remember that birth control package inserts list a long range of possible side effects, from mild stuff like bleeding gums to eye discomfort and sun sensitivity. Those warnings are there for a reason, even though not everyone gets every side effect on the list.

Smoking weed on the pill: the bottom line

Right now there isn't enough information to say anything definitive about how CBD interacts with birth control. There are a few isolated studies, but no firm conclusions yet.

Still, it's smart to be cautious when combining CBD with hormonal birth control, and to consider progestin-only methods and/or condoms as a backup if you use CBD regularly. Your doctor or pharmacist can help you sort out what's right for you.