Can You Overdose on CBD and How Much CBD Should You Take for Your Condition?

The dosage of CBD remains one of the most puzzling subjects and is high on the list of concerns of our industry’s consumers. Here is what everyone who takes CBD should know. First of all, you can not die of an overdose on CBD. Second of all, don’t forget CBD is considered a medicine, and as such, should be taken with caution. In this article, we will try to give you the most detailed information on how much CBD you should take for your condition.

There’s been a light stir in the industry lately when research confirming previous findings was published and proved that CBD, if taken excessively, can damage your liver.

How much CBD can damage your liver?

A paper published in Clinical Pharmacology & Therapeutics on the 6th of October 2020, as a result of randomized controlled trials of CBD in patients with Lennox‐Gastaut and Dravet syndromes, showed that the administration of 1500 mg/day for 3,5 weeks is causing liver damage. Five out of 16 participants in the study met the international consensus criteria for drug-induced liver injury, and some had symptoms consistent with hepatitis or hypersensitivity.

However, the dose given to the participants in the trial by far exceeded the recommended dosage and can only be compared with the recommended dosage for the treatment of schizophrenia in obese people, which must be taken into account when speaking about the subject.

Apart from this, everyone who is taking CBD must know that there might be mild side effects such as sleepiness, diarrhea, or increased temperature. When taken with other drugs, clinically significant drug‐interactions pose a low risk

In case you are starting your CBD treatment with CBD oil, which is the favorite choice of European consumers, it is advised to try holding it under your tongue or swishing it around your mouth before swallowing.

CBD dosage: How much CBD should you take for your condition?

The Mayo Clinic has published suggestions of CBD dosages based on scientific research, publications, traditional use, and expert opinion.

The following are their dosage recommendations for various illnesses:

  • Loss of Appetite in Cancer Patients: 2.5mg of THC (orally), with or without 1mg of CBD for six weeks. [S]
  • Chronic Pain: 2.5-20mg of CBD [with or without THC] (orally). [S]
  • Epilepsy: 200-300mg of CBD (orally) daily. [S]
  • Movement Problems Due to Huntington’s Disease: 10mg of CBD per kg of body weight daily for six weeks (orally). [S]
  • Sleep Disorders: 40mg-160mg of CBD (orally). [S]
  • Multiple Sclerosis (MS) symptoms: Cannabis plant extracts containing 2.5-120 milligrams of a THC/CBD combination daily for 2-15 weeks. Patients typically use eight sprays within any three hours, with a maximum of 48 sprays in any 24 hours. [S]
  • Schizophrenia: 40-1,280mg oral CBD daily. [S]
  • Glaucoma: A single sublingual CBD dosage of 20-40mg (>40 mg may increase eye pressure). [S]

Arthritis: American Arthritis Foundation advises starting with just a few milligrams of CBD in the sublingual form twice a day. If relief is inadequate after one week, increase the dose by that same amount. If needed, go up in small increments over several weeks. If you find relief, continue taking that dose twice daily to maintain a stable level of CBD in the blood. 

As it’s obvious from the above figures and you can find out from my previous articles, the exact dosage depends not only on the condition itself but the symptoms you are targeting. Of course, what also needs to be taken into account is your body weight.

How to calculate the amount of CBD in your oil?

To add to the overall confusion, what you also have to have in mind when deciding about your dose is that different products contain different percentages of CBD. When the industry just started developing, the idea was that a higher percentage of CBD in the product automatically means better value for the consumer. This is not entirely correct. The exact dosage you need can be taken in through any product of any CBD percentage, but you need to calculate how much of the particular product you need, taking into account its CBD concentration. For example, if your targeted dose is 100 mg of CBD, and you are using a 10% CBD product, you should be taking 1g of the product a day. If you are using 5% CBD, you should be taking 2g a day, etc.

So, if your targeted dose is higher than the average, it is advised to buy a product containing a higher percentage of CBD.

If you can’t be sure about the calculation, here are formulas you can use to calculate your daily CBD intake, once you decided about the targeted dose and checked the brand’s label stating the amount of CBD in the product:

If the amount of CBD in your oil is expressed in mg (usually per packaging – e.g. 300 mg in 10 ml, or 1000 mg in 30 ml), then the amount in one drop is:

(amount in mg per packaging – e.g. 300 mg) ÷ (packaging volume – e.g. 10 ml) x 0,05 (Volume of 1 drop in ml) = amount in mg of CBD in one drop

300 ÷10 x 0,05=1,5 mg – in 1 drop of oil labeled as 300 mg in 10 ml bottle is 1,5 mg of CBD

If the amount of CBD in your oil is expressed in %. In that case, the volume of the packaging bottle is not important. In this calculation, we will convert volume to mass (ml to g), and to be able to do this accurately we have to know the specific gravity of your CBD oil. All the oils have a specific gravity of less than 1 g/ml, accurate value depends on the formulation of your product. Most of the CBD oils have specific gravity between 0,92 g/ml – 0,96 g/ml, in our calculation we will use 0,94 conversion factor.

Amount in one drop (expresed in mg) in e.g. 15% oil is:

0,05 (volume of a drop) x 0,94 (specific gravity of product) x 15 ÷ 100 (percentage) x 1000 ( conversion factor g to mg) = amount in mg of CBD in one drop

0,05×0,94×15÷100×1000= 7,05 mg – one drop of oil labeled as 15% contains 7,05 mg of CBD

How much CBD should you take per kilo of your weight?

The answer to this question comes from the first study that compiled and compared all publications in which CBD was administered in clinical populations. This study represents a systematic review of 35 articles, comprising a total number of 1223 participants.

Here is the data of CBD efficiently administrated for different conditions covered by these researches:

  • Anxiety 400 mg (6.7 mg/kg)
  • Cannabis dependency 300 mg/d increased to 600 mg/d (5-10 mg/kg/d)
  • Schizophrenia 1000 mg/d (16.7 mg/kg/d) 8 wk
  • Lennox–Gastaut syndrome ages 2–55 y 10 to 20 mg/kg/d 14 wk
  • Psychosis in Parkinson’s disease, 150 mg/d, increased by 150 mg each week to a total of 400 mg/d (6.7 mg/kg/d) 4 wk
  • Parkinson’s disease 100–400 mg/d (3.3 mg/kg/d) 4 wk

(Improvement of dyskinesia has been observed with up to 200 mg/d, but worsening of Parkinson disease symptoms occurred with 300–400 mg/d)

  • RBD (sleep disorder) in Parkinson’s disease 75 mg/d (1.25 mg/kg/d) 6 weeks
  • Dystonic movement disorder 100–600 mg/d, increased weekly (1.7–10 mg/kg/d) 6 wk
  • Sturge–Weber syndrome 5–25 mg/kg/d 14 wk
  • Graft-versus-host disease (GVHD) – an immune condition that occurs after transplant procedures 300 mg/d (5 mg/kg/d) 37‐day
  • Brain tumor-related epilepsy 10–50 mg/kg/d for 2–10 months
  • Febrile infection‐related epilepsy syndrome 15–25 mg/kg/d up to 48 weeks
  • Anxiety and insomnia in PTSD, child 25 mg/d (0.6 mg/kg/d) 5 months
  • Seizures, 10‐month old infant 25 mg/kg/d 6 months
  • Meige syndrome 100 mg/d increased to 400 mg/d (6.6 mg/kg/d) long-term (50% improvement in spasm frequency and severity)

CBD dosage: What is the right dose for healthy people?

Of course, you don’t have to be ill to consume CBD. Many people take CBD to improve their lives and general well-being or just to make sure they are sufficiently equipped for dealing with everyday stress. This is the most recent systematic review of human trials, which can help you find your perfect dose. 

The following CBD dosage has been found to be efficient in healthy volunteers:

Anxiety in healthy volunteers 100, 400, and 900 mg; a single dose

(300 mg reduced subjective anxiety measures and presented lower sedation levels when compared with clonazepam. This was not observed with 100 and 900 mg)

Healthy volunteers reacting to negative stimuli 300, 600, and 900 mg; a single dose

Healthy volunteers with anxiety during public speaking, 300 mg; a single dose

Consolidation of extinction learning for healthy volunteers, 32 mg; a single dose

Emotional processing in cannabis users 16 mg; a single dose

And for the smokers, these are the recommended doses based on the evidence from clinical trials:

Tobacco smoking 400 µg; 1-week inhalation

Nicotine withdrawal 800 mg; a single dose

British Food Standards Agency (FSA) recommends that healthy adults should not take more than 70mg of CBD a day, which is about 28 drops of 5% CBD. 

Reviewed by Sasha Bajilo, founder of ILESOL Pharmaceuticals, an industrial scale producer of CBD products and formulations. Expert on Hemp/Cannabis policy, member of the Croatian Ministry of Health regulatory commission for medical cannabis.