Delta-9 is a chemical in cannabis and hemp plants. It can have an intoxicating effect and may cause some side effects.

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Cannabis and hemp plants consist of dozens of cannabinoids. Cannabinoids are chemicals that affect the body in various ways. Two well-known cannabinoids are cannabidiol (CBD) and tetrahydrocannabinol (THC).

A few different forms of THC are in cannabis plants. The most abundant form of THC is delta-9. When people refer to the effects of THC, they’re usually talking about delta-9.

Other forms of THC, such as delta-8 and delta-10, have similar chemical structures to delta-9, but their effects are usually different.

The chemical formula of delta-9 is C₂₁H₃₀O₂. This is the same as delta-8, except that one of the carbon-carbon double bonds is in a different position.

The majority of research on THC specifically looks at delta-9, so it’s the most well-studied and well-known form of THC.

THC is the cannabinoid responsible for making people experience an intoxicating effect when they consume cannabis.

The most abundant form of THC is delta-9, which has an intoxicating effect. In other words, delta-9 is what makes you feel high.

After consuming cannabis, you might experience the following positive short-term effects:

  • altered perception of time and events
  • giddiness
  • increased focus
  • relaxation

However, THC can also have some side effects, including:

Like CBD, people have associated delta-9 THC with a number of potential medical benefits.

Most people can tolerate delta-9 THC well, but it’s important to be aware of the risks and potential side effects.

THC triggers your brain to release large amounts of dopamine, a “feel good” chemical. This is why being high feels so pleasant to many people.

But this dopamine release comes with a risk. Between 9% and 30% of people who use cannabis may develop cannabis use disorder.

It’s possible to experience cannabis withdrawal symptoms if you go from using cannabis regularly to stopping use.

Yes — delta-9 THC has been associated with a wide range of potential medical benefits.

According to 2021 research, THC might be able to treat:

The Food and Drug Administration approved some medications containing THC to treat medical conditions. For example, experts use a synthetic form of delta-9 THC to create dronabinol (Marinol), which they use to stimulate appetite in people with HIV, people undergoing chemotherapy, and people with anorexia.

Yes. THC, including delta-9 THC, can have side effects.

Many of the common side effects of THC are temporary. These side effects can include:

  • anxiety
  • dry mouth
  • increased appetite and heart rate
  • memory loss
  • red eyes
  • slowed reaction times

Lastly, although there have been no recorded deaths from cannabis overdosing, it’s definitely possible to overdo it and misuse cannabis. Using too much cannabis might make you feel anxious, confused, or dizzy. To avoid an unpleasant experience, pace yourself.

In rarer cases, high dosages of cannabis can also cause:

  • hallucinations
  • paranoia and panic attacks
  • nausea and vomiting

Usually, negative experiences with cannabis go away as you come down from the high. If you’re experiencing a bad high, try to relax and hydrate. Remember that the effects are temporary.

If possible, consider discussing THC with a doctor or another healthcare professional before trying it for yourself, especially if you’re hoping to use it to treat a medical condition. Look for a knowledgeable cannabis-friendly doctor.

Beyond the above-mentioned side effects, there are some risks of delta-9.

If you consume cannabis by smoking, remember that smoking anything — including cannabis — can affect your lungs and throat. Some 2018 research suggested that smoking cannabis can cause bronchitis, and it might increase your chances of developing chronic obstructive pulmonary disease.

Early cannabis use might also affect brain development. Some research from 2014 suggested that cannabis can affect your brain development if you use it in adolescence.

Researchers found that people who started using cannabis in their teens were more likely to experience memory and learning difficulties, but it’s unclear whether these effects are permanent.

Naturally-occurring delta-9 is different from the synthetic product called delta-9 THC-O acetate, which is an oily brown residue sold as a vaping product or used in gummies. Research is limited on the strength and risks of this chemical.

The National Poison Control Center has issued a statement recommending caution for those who manufacture or use delta-9 THC acetate.

Delta-9 THC isn’t federally legal in the United States. However, each state has its own laws.

In some states, cannabis and cannabis derivatives like delta-9 THC are only legal for medical use, while in others, it’s legal for recreational use.

Cannabis laws are constantly changing. You can find out about your state’s current cannabis laws by looking at Norml’s helpful map.

The FDA does not regulate delta-9 THC products. It’s important to research a company or vendor before purchasing their products.

When it comes to buying THC products, it’s best to purchase from reputable companies. It’s safer to buy products tested by a third-party lab. You should be able to read these lab reports on the company’s website.

Of course, if you’re purchasing cannabis from a local grower, they might not be able to have their products lab-tested. This doesn’t necessarily mean that their cannabis is bad.

You can ascertain quality by:

  • inquiring how their products are grown
  • asking them which product to choose for your desired effects (e.g. relaxation, productivity, sleep)
  • talking with their other customers — getting a recommendation is always a good idea

If you’re not used to using cannabis, it’s safer to start with a low dosage. Because of this, it’s best to go with a product that is not very high in THC. Usually, 1 to 2 milligrams is a good starting point. You can gradually increase your dosage if needed.

If you have a lung condition, or if smoking irritates your chest and throat, it might be best to avoid smoking cannabis and instead opt for THC-infused edibles or tinctures. Bear in mind that cannabis edibles take longer to kick in than smoked cannabis.

Is delta-9 the same as THC or CBD?

Delta-9 is a form of THC. It’s not the same as CBD.

While delta-9 is intoxicating, CBD is not.

What’s the difference between delta-9 and delta-8?

Chemically, delta-9 and delta-8 are very similar. They share a chemical formula, which is C₂₁H₃₀O₂. The difference between delta-8 and delta-9 is that one of the carbon-carbon double bonds is in a different location.

In terms of bodily effects, both delta-9 and delta-8 are intoxicating. However, delta-8 seems to be less potent than delta-9, according to anecdotal accounts. Some people claim that they have fewer side effects with delta-8 compared with delta-9, according to this 2022 study.

D8-THC does not naturally occur in large amounts in the cannabis plant like D9-THC and many of the D8 products on the market are synthetic and may carry additional safety concerns.

Experts need more research to determine the exact differences between the effects of delta-9 and the effects of delta-8.

Is delta-9 safe?

You can safely consume delta-9. But it has some potential risks and side effects.

Common short-term side effects of delta-9 THC include:

  • anxiety
  • dry mouth
  • increased appetite and heart rate
  • memory loss
  • red eyes
  • slowed reaction times

Rarer short-term effects of cannabis can include:

  • hallucinations
  • paranoia and panic attacks
  • nausea and vomiting

If you smoke delta-9 THC — that is, if you smoke cannabis — it can irritate your respiratory system. Smoking cannabis has been linked to bronchitis and COPD.

If you want to use delta-9 THC products for medical reasons, it’s best to speak with a cannabis-friendly clinician before using it yourself.

Is delta-9 legal?

In the U.S., delta-9 THC products are legal in some states and illegal in others.

In some states, cannabis is legal for medical purposes, and in others, it’s legal for recreational purposes. Take a look at Norml’s map of cannabis laws to learn more about your state’s policies on cannabis use.

Can delta-9 get you high?

Yes! In fact, delta-9 is the most abundant form of THC in cannabis plants. THC is the chemical that makes cannabis intoxicating.

Delta-9 THC is the most common and well-studied form of THC. It’s an intoxicating chemical that people can use for medical purposes.

As always, it’s important to exercise caution when using cannabis products. Only buy cannabis from reputable vendors, and avoid taking too much at once.


Sian Ferguson is a freelance health and cannabis writer based in Cape Town, South Africa. She’s passionate about empowering readers to take care of their mental and physical health through science-based, empathetically delivered information.