If you use cannabis on a regular basis, it’s important to understand the risks of developing cannabinoid hyperemesis syndrome (CHS).

Cannabis has become an extremely popular substance due to the legalisation of this drug in many countries.

Currently, it is illegal to use cannabis recreationally in the UK. However, the number of regular users has skyrocketed in recent years.

As a result, cannabinoid hyperemesis syndrome is becoming more common and many people are seeking medical treatment for this condition.

Read more to understand more about cannabinoid hyperemesis syndrome including symptoms, diagnosis and treatment.

Understanding cannabinoid hyperemesis syndrome (CHS)


What is cannabinoid hyperemesis syndrome?

Cannabinoid hyperemesis syndrome is a condition that can develop if you use cannabis regularly for a long period of time.

CHS is characterised by extreme vomiting as well as other symptoms including abdominal pain and dehydration as a result of the frequent vomiting. [1]

It is a cyclical condition, meaning that it can occur and reoccur seemingly at random.

Many people believe that they have the flu when they begin to experience the symptoms of cannabinoid hyperemesis syndrome, but after repeated episodes of vomiting, they may seek a formal diagnosis.

It is important to seek medical treatment if you suspect you are suffering from cannabinoid hyperemesis syndrome, as it can have serious health consequences if not properly treated.

What causes cannabinoid hyperemesis syndrome?

It is not known exactly what causes cannabinoid hyperemesis syndrome and why only certain people seem to develop it.

Some theories point towards a genetic predisposition, but this has not been studied enough to serve as a true answer.

Other experts believe that CHS could be the result of overstimulating your endocannabinoid system with frequent and chronic cannabis use.

The endocannabinoid system (ECS) regulates some of our most important bodily functions and it is thought that too much cannabis over a long period of time may disrupt it, leading to vomiting and other symptoms. [2]

The main active ingredient in cannabis, THC, is usually an effective anti-nausea solution. However, some studies indicate that repeated exposure to THC can actually have the opposite effect.

How common is cannabinoid hyperemesis syndrome?

Cannabinoid hyperemesis syndrome is rare, affecting only a small number of chronic cannabis users.

It is difficult to get an idea of the true amount of people who suffer from this condition, as many cases are likely not reported or potentially misdiagnosed.

One study found that up to 6% of people who attend A&E due to vomiting are suffering from cannabinoid hyperemesis syndrome.

However, many people may attempt to treat themselves at home instead of seeking medical treatment.

Cannabinoid hyperemesis syndrome is a relatively new illness, and more studies need to be conducted to understand the proportion of cannabis users affected.

Who can develop cannabinoid hyperemesis syndrome?

Anyone who uses cannabis regularly can develop cannabinoid hyperemesis syndrome, but it is predominantly found in adults who have been using cannabis at least once a week since their teenage years.

One study found that one-third of people who use cannabis at least 20 days per month showed symptoms of cannabinoid hyperemesis syndrome.

Not every cannabis user develops CHS, but the reasons for this are currently unknown.

It is also unknown whether smoking, vaping or consuming cannabis can increase your chances of developing CHS.

What are the risk factors for developing cannabinoid hyperemesis syndrome?

The main risk factor for developing cannabinoid hyperemesis syndrome is using cannabis regularly, particularly daily use.

As mentioned above, you may also be more likely to develop CHS if you have been using cannabis since adolescence.

If you have a family history of addiction, this may also increase your chances of developing cannabinoid hyperemesis syndrome as you may be predisposed to cannabis dependency.

While regular and frequent use of cannabis is the most likely reason for developing cannabinoid hyperemesis syndrome, it is possible to develop CHS from any amount of cannabis use.

Symptoms of cannabinoid hyperemesis syndrome (CHS)


What are the symptoms of cannabinoid hyperemesis syndrome?

Cannabinoid hyperemesis syndrome is a cyclical condition, which means that it comes and goes in waves.

Sometimes you will have no symptoms and will be able to live a normal life. But eventually, the cycle of vomiting will start again and make you feel extremely unwell.

The most common symptoms of cannabinoid hyperemesis syndrome are listed below:

  • Frequent nausea
  • Loss of appetite
  • Weight loss
  • Vomiting repeatedly and uncontrollably
  • Signs of dehydration

If you are experiencing these symptoms and have been using cannabis regularly for a long period of time, you may have developed CHS.

What are the phases of cannabinoid hyperemesis syndrome?

Cannabinoid hyperemesis syndrome often presents in three distinct stages, each with its own symptoms.

These are known as the prodromal phase, the hyperemetic phase and the recovery phase.

Prodromal phase

Often lasting for months or even years, this is the initial stage of cannabinoid hyperemesis syndrome.

You may experience nausea, particularly in the mornings, as well as stomach pain. Despite these symptoms, most people are still able to eat their usual diet and continue to live normally.

Some people develop a fear of vomiting during this time due to the constant sensation of nausea that they are experiencing.

It’s common for sufferers in the prodromal phase to continue using cannabis in an attempt to ease the symptoms of nausea.

Hyperemetic phase

The hyperemetic phase is the second stage of cannabinoid hyperemesis syndrome, and this will likely last until you stop using cannabis.

You may experience frequent vomiting and extreme nausea as well as severe stomach and abdominal pain.

It will be difficult to continue with your normal diet and you will likely experience a loss of appetite.

This stage is cyclical, meaning that you may feel better for a short while until the symptoms begin again.

Recovery phase

Once you seek medical treatment for cannabinoid hyperemesis syndrome and stop using cannabis, you will enter the recovery phase.

You will stop vomiting, your appetite will come back and you will begin to feel better.

It’s important that you continue to drink plenty of fluids in order to replenish what was lost during the hyperemetic phase.

If you begin using cannabis again in the future, you may begin to develop symptoms of CHS again and enter the prodromal or hyperemetic phase once again.

How can I deal with the symptoms of cannabinoid hyperemesis syndrome?

Many people find relief from the symptoms of cannabinoid hyperemesis syndrome by taking long hot baths or showers.

However, you will need to be careful not to increase your risk of dehydration even further with the hot water.

To combat this, continue to sip water throughout your time in the shower or bath.

If you have been vomiting for more than a day, you should visit your doctor or emergency department for medical treatment as you are at risk of developing CHS complications.

What are the potential complications of cannabinoid hyperemesis syndrome?

While vomiting is extremely unpleasant, as a one-off it doesn’t usually cause any major complications.

But when the vomiting is prolonged and frequent, such as in the case of cannabinoid hyperemesis syndrome, it can lead to potentially dangerous complications.

If you vomit too much, you can become dehydrated. This means that your body does not contain enough water to function effectively.

Your body is made up of two-thirds water and this helps to keep your eyes, joints and mouth lubricated as well as flushing waste out of your system. [3]

Some of the symptoms of dehydration include the following:

  • Feeling extremely thirsty
  • Dizziness and lightheadedness
  • Passing urine infrequently
  • A dark tinge and strong smell to your urine
  • Having a dry mouth

Vomiting too much can also cause an electrolyte imbalance in your body, another potentially dangerous condition.

This can lead to several issues including the following:

  • Seizures
  • Kidney failure
  • Shock
  • Swelling of the brain

Due to these potential complications, it is recommended that you seek medical assistance if you begin to experience the symptoms of cannabinoid hyperemesis syndrome.

How can I prevent cannabinoid hyperemesis syndrome?

The only way to prevent cannabinoid hyperemesis syndrome is to completely stop using cannabis.

Cutting down on your usage is not enough – to remove the risk of developing this condition, you must no longer use cannabis in any form.

We understand that this can be difficult, particularly if you have used cannabis regularly for many years without developing CHS.

If you have developed a psychological dependency on cannabis, willpower alone may not be enough to help you stop using it.

We recommend looking into your therapy options or considering an outpatient rehab programme for cannabis addiction.

Our team at OK Rehab are here to help with any questions you may have – give us a call today on 0800 326 5559 and find out how you can successfully stop using cannabis.

Treating cannabinoid hyperemesis syndrome (CHS)

Group holding hands

How is cannabinoid hyperemesis syndrome diagnosed?

Vomiting is a fairly common symptom that can be attributed to a range of illnesses, so a number of tests will need to be performed before a diagnosis of cannabinoid hyperemesis syndrome is given.

However, there are no specific tests that can confirm whether you have CHS. You will only know for sure once you stop using cannabis and your symptoms disappear.

First, doctors will need to rule out any medical emergencies.

They may examine your stomach and speak to you about any past illnesses or your family medical history.

They may also run several tests including the following:

  • Blood tests
  • CT scans
  • Drug tests
  • Pregnancy test
  • Stomach x-rays
  • Upper endoscopy

You may find it difficult to receive a diagnosis of cannabinoid hyperemesis syndrome, as it is less well-known condition.

For the best chances of receiving a correct diagnosis, you may need to speak to a professional gastroenterologist.

How is cannabinoid hyperemesis syndrome treated?

It is possible to treat cannabinoid hyperemesis syndrome, both at home and in a hospital setting.

In severe cases in which you have been vomiting frequently and developed dehydration, you may need to spend some time in the hospital.

Medical staff will replenish your fluids and rebalance your electrolytes using an IV drip, and may be able to prescribe medication to prevent you from vomiting.

They can also give you pain medication as well as treat any stomach inflammation.

You will not be able to use cannabis while in the hospital, and it is recommended that you stop using it altogether. Otherwise, your symptoms are likely to return.

You can also treat the symptoms of nausea by taking long hot showers or baths, and within a few days, you should begin to feel better.

Can I treat cannabinoid hyperemesis syndrome at home?

Cannabinoid hyperemesis syndrome can be treated at home, but it’s important that you seek medical assistance if you have any of the following symptoms:

  • Dark urine
  • Trouble passing urine
  • Feeling dizzy
  • Fainting
  • Confusion
  • Feeling extremely tired
  • Breathing quickly
  • Increased heart rate

These may be signs of dehydration, which can be dangerous if not properly treated.

As mentioned above you can take long hot baths or showers, making sure to sip on water and rest as much as possible.

Of course, you will need to stop using cannabis if you have developed CHS otherwise your symptoms will continue to repeat.

How soon after cannabinoid hyperemesis syndrome treatment will I feel better?

Once you stop using cannabis, you should begin to feel better within 10 days.

You will be able to resume your normal eating and bathing habits during this time, but you should take it easy while your body recovers.

It is also recommended that you avoid alcohol and other substances while you recover from cannabinoid hyperemesis syndrome.

If you developed dehydration due to CHS, it may take a little longer for you to fully recover. Follow your doctor’s orders, make sure to drink enough fluids and rest until you are feeling better.

The same is true if you had developed a psychological dependence on cannabis – you may experience cravings and other withdrawal symptoms for a few weeks, but with time and the right support these should fade over time.


[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5330965/

[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4361109/

[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2908954/