Disclosure: BDI.ie is run by the team behind Dr. Hemp Me and CBD Éire. Where we mention those brands, we have a commercial interest. More about who we are.
Last reviewed: October 2026
It is a sensible question to ask about any supplement: what happens if I take too much? With CBD, the short answer is that a fatal overdose has not been reported, but taking more than the recommended amount can cause side effects, interact with medicines and, with poorly made products, expose you to THC. This guide explains the risks honestly and how to stay within sensible limits.
Can you overdose on CBD?
There are no reliable reports of anyone dying from CBD alone. In 2018 the World Health Organization concluded that CBD is generally well tolerated and shows no potential for abuse or dependence. That is reassuring, but it is not the same as saying any amount is safe. In clinical studies of a prescription CBD medicine, which uses doses far higher than food supplements, side effects were common and some patients developed raised liver enzymes.
So the realistic risk with CBD is not a dramatic overdose. It is taking more than you need, feeling unwell, or running into problems with other medicines.
What happens if you take too much CBD?
People who take more CBD than recommended most often report:
- Drowsiness or tiredness.
- Diarrhoea or an upset stomach (sometimes from the carrier oil as much as the CBD).
- Changes in appetite.
- Feeling light-headed.
- Dry mouth.
These usually pass as the CBD wears off. If you have taken a large amount and feel unwell, stop taking it, drink water, do not drive, and contact your GP or pharmacist. In an emergency, call 112 or 999.
The real risk: THC in poorly made products
Many cases of people feeling “high”, anxious, dizzy or very unwell after a “CBD” product turn out to involve THC or synthetic cannabinoids, not CBD. Products bought from social media, market stalls or unknown websites may contain THC, HHC or other substances not listed on the label. HHC became a controlled drug in Ireland in July 2025. Children who eat cannabis-infused sweets have been admitted to Irish hospitals.
Always use products with an independent lab report showing THC is not detected, and keep all CBD products out of reach of children.
Medicine interactions
CBD is broken down in the liver by the same enzymes that process many common medicines. Taking CBD can change the levels of some medicines in your blood. Medicines where this matters include blood thinners such as warfarin, some anti-epileptic medicines, some heart medicines, some antidepressants and sedatives. Before taking CBD alongside any regular medication, ask your GP or pharmacist.
Liver health
In trials of high-dose prescription CBD, some people developed raised liver enzymes, especially when they also took certain other medicines. At the much lower amounts in food supplements this appears less likely, but if you have a liver condition, drink heavily or take medicines that affect the liver, speak to your doctor before using CBD.
How much CBD is sensible?
The simplest rule is to follow the recommended daily serving on the label of a properly labelled Irish or EU product and not exceed it. Food supplement labels are required to include a recommended daily amount and a warning not to go above it. Start at the lower end, keep it steady and do not double up on days when you feel you need “more”.
Be careful if you use more than one CBD product at once, for example oil plus gummies plus a CBD drink. Add up the total CBD across all of them.
Who should avoid CBD
- Pregnant or breastfeeding women.
- Children (CBD food supplements are not intended for children).
- Anyone taking medicines that interact with CBD, unless their doctor agrees.
- People with liver disease, unless their doctor agrees.
- Anyone who needs to pass drug tests and cannot be certain their product is THC-free.
CBD and alcohol
Both CBD and alcohol can cause drowsiness, and combining them may increase that effect. Alcohol is also processed by the liver. Avoid mixing them, especially if you plan to drive.
CBD and driving
CBD itself is not intoxicating, but if it makes you drowsy, do not drive. Products containing THC can impair driving and lead to a positive roadside drug test, which is an offence in Ireland regardless of whether you feel impaired. Another reason to insist on a lab report.
Pets and CBD
Dogs and cats are much more sensitive to THC than people. If a pet eats a human CBD product, especially gummies or anything that might contain THC or xylitol, call your vet straight away. See our guide to CBD and dogs in Ireland.
How to stay safe
- Buy from established sellers with independent lab reports.
- Check THC is not detected.
- Read the label and keep within the recommended daily serving.
- Tell your GP or pharmacist you are taking CBD.
- Do not mix with alcohol, and do not drive if drowsy.
- Store safely away from children and pets.
Why labels and lab reports matter for safety
Most of the safety problems linked to “CBD” come down to products that are not what they claim to be. Independent testing of CBD products in Europe and the UK has repeatedly found some products with far more or far less CBD than the label states, and some containing THC. When the amount on the label is wrong, following the recommended serving does not protect you. A certificate of analysis from an independent laboratory, with a batch number that matches your bottle, is the simplest protection you have.
A good lab report shows the CBD content (which should be close to the label), the THC result (which should be “not detected” or below the limit of quantification), and ideally tests for contaminants such as pesticides, heavy metals and residual solvents.
Different forms, different risks
Oils are easy to measure by the drop, which makes it easy to stay within limits. Gummies taste like sweets, so it is easier to eat more than intended and they are attractive to children. Drinks and foods containing CBD may not state the amount clearly, and adding them on top of other CBD products can push your total up without you noticing. Vapes are not a recommended way to use CBD; vaping carries its own lung risks and illegal vape cartridges have been found to contain synthetic cannabinoids.
Myths about CBD and overdose
- “It’s natural, so you can’t take too much.” Plenty of natural substances cause harm at high doses.
- “More CBD means better results.” There is no good evidence that taking more than the recommended serving brings extra benefit, and side effects become more likely.
- “If it’s sold in a shop, it must be safe.” Quality varies. Check the lab report.
Talking to your pharmacist about CBD
Irish pharmacists are well placed to check for interactions, and the conversation takes only a few minutes. Bring the bottle or a photo of the label, a list of every medicine and supplement you take (including over-the-counter painkillers and herbal products), and tell them how much CBD you plan to take each day. Ask whether any of your medicines are processed by the liver enzymes CBD can affect, and what signs would mean you should stop.
Frequently asked questions
Can you overdose on CBD?
No deaths from CBD alone have been reliably reported, but taking too much can cause side effects such as drowsiness, diarrhoea and appetite changes.
What is the maximum amount of CBD per day?
Follow the recommended daily serving on your product label and do not exceed it. Add up CBD from all products you use.
What should I do if I took too much CBD?
Stop taking it, drink water, rest and do not drive. Contact your GP or pharmacist if you feel unwell, or call 112 or 999 in an emergency.
Can CBD damage your liver?
High doses in prescription trials raised liver enzymes in some people. If you have liver problems or take interacting medicines, speak to your doctor first.
Can CBD interact with my medication?
Yes, CBD can affect how some medicines are processed, including blood thinners and some epilepsy medicines. Ask your pharmacist.
Why did a CBD product make me feel high?
CBD does not cause a high. The product may have contained THC, HHC or another substance. Stop using it.
Is it safe to take CBD every day?
Many people take it daily within the recommended serving. Check with your GP if you take medicines or have health conditions.
What if my child ate a CBD gummy?
Contact your GP, the out-of-hours service or the National Poisons Information Centre on (01) 809 2166, and keep the packaging.
Related guides
This guide is for general information only and is not medical advice. CBD products sold in Ireland are food supplements or cosmetics, not medicines. Speak to your GP or pharmacist before using CBD, especially if you take medication, are pregnant or breastfeeding.