Cannabidiol or CBD is one of the many cannabinoids found in the Cannabis sativa plant, popularly known as marijuana.
Its advantages on health have now been established by numerous studies. To benefit from its effects, it is imperative to know the proper dosage.
As with most natural products and complementary medicines, CBD does not have any particular dosage for the treatment of any health condition.
The legal and approved usage of CBD in the medical community has just begun with scientists proving its multiple health benefits.
Most of the benefits have been established by preliminary and preclinical studies and there are few studies on humans.
Based on available research in clinical trials with positive outcomes, the dosages of CBD have been formulated in this article.
Why CBD Dosage Varies?
The dosage and duration of intake depend on several factors:
Purpose of use
Due to its many health benefits, CBD can be used both, for the prevention and treatment of certain diseases.
Preventive dosage usually requires a regular intake of small amounts of CBD.
On the other hand, for a therapeutic effect, larger doses might be required, but for shorter durations, till the desired benefit is achieved.
Mode of intake
CBD can be used orally, topically, intravenously or by vaporization, based on which the dose can be increased or decreased.
Oral intake may require relatively larger doses depending on how much the body is able to absorb and utilize in a single dose.
Here, CBD takes time to enter the bloodstream (about 1-2 hours).
In oromucosal intake, tinctures or mouth strips are not swallowed but kept below the tongue.
CBD enters the blood from mucous membranes directly and hence, smaller amounts required.
Vaporization has been identified as an effective and instant method for CBD delivery.
This requires a small amount of CBD which can be taken in the form of vapors from cigarettes, sprays or inhalers. CBD enters the bloodstream from the lungs.
In extreme cases and for instant delivery, CBD can be injected intravenously in low doses.
The topical dose is required in skin conditions and for relieving pain in a particular body area.
Here, CBD makes direct contact with the body cells, and thus lower amounts are required. However, CBD does not enter the bloodstream and the effect is localized only.
The weight of an individual
Studies conducted with CBD have used doses based on the weight of the subjects.
A particular amount of CBD is delivered per kg of body weight to the individuals.
This means that an overweight person may require a larger dose of CBD and vice versa.
The health condition of an individual
The dosage of CBD depends on the type and severity of the disease for which treatment is sought, medications, medical history, metabolic rate, allergies and the prevalence of other health conditions in the individual.
Concentration and composition of CBD oil
CBD –rich hemp oil is available in different concentrations.
The oil may also contain other cannabis extracts like THC which is the psychoactive component. Based on this composition, the dosage may vary.
What are the different ways in which CBD can be taken?
CBD is extracted from the Cannabis plant in the form of oil or powder. It can then be taken in the following ways:
Oral: CBD can be taken in the form of oil capsules, pills, candy bars, gums, oil paste, tincture drops, sprays or mouth strips.
CBD products can be ingested or placed below the tongue (sublingual delivery) for optimum absorption.
Inhalation: CBD extracts or oil can be put in a vaporizer/inhaler and the fumes can be inhaled. CBD cigarettes can also be smoked.
Topical: CBD has been found to be permeable to human skin.
CBD oil, lotions, creams, gels, ointments, balms or patches can be applied topically.
Intravenous: CBD can be directly injected into the body to obtain instant plasma concentrations. However, this should be done only by an experienced medical practitioner.
Can CBD be taken with THC?
Many studies have used CBD in combination with THC (Tetrahydrocannabinol) and achieved positive results.
This is because THC also has many health benefits.
THC is the psychoactive component of the cannabis plant and is known to cause psychosis.
However, studies have also reported that CBD, when given with THC, modulates its psychotic effects.  
Many formulations containing both CBD and THC have been used in numerous clinical trials for the treatment of diseases.
It is usually used in the form of oromucosal sprays by the name of Nabiximols or Sativex.
How much CBD to take for a particular health condition?
A note on how we researched on the dosages.
There is no “prescribed” dosage of CBD. To find out the dosages, we analyzed 300+ research papers with usage of CBD in various forms for a variety of health issues. This data was collated and then presented here.
Thus, the following doses of CBD have been used in clinical trials and human studies. This also means, they were done under control conditions and thus should not be replicated unless under medical supervision.
The dose of Pure CBD (Oral doses)
|Health Issue||CBD Dosage|
|Blood pressure||Single dose of 600 mg CBD can reduce blood pressure by 5mmHg|
|Improving lipid and glucose parameters in diabetes||100 mg CBD taken twice daily|
|Epilepsy and related disorders||1-50 mg CBD per kg of body weight per day, based on tolerability levels. CBD can be taken for up to 18 weeks till positive results are noticed.|
|Parkinson’s disease||150-300 mg CBD per day for symptomatic relief. Doses of more than 300 mg can aggravate Parkinson’s symptoms.|
|Schizophrenia||600-1500 mg CBD per day to treat psychosis|
|Anxiety, panic and related disorders||300-600 mg CBD per day|
|Insomnia||160 mg CBD before sleep|
|Fear memories extinction||32 mg CBD|
|Cigarette smoking/Nicotine addiction||CBD inhaler delivering 400 µg CBD per inhalation, whenever the patient feels the urge to smoke|
|Cannabis addiction||300-600 mg CBD per day orally for treating cannabis withdrawal symptoms. Inhaling 16 mg CBD per day reduces cannabis use or addiction|
Dose of CBD+THC Spray
(Oromucosal/Sublingual spray- Considering each spray delivers 2.7 mg/ml THC and 2.5 mg CBD)
|Health Issue||CBD Dosage|
|Pain and spasticity in Multiple sclerosis||Spray on the affected area depending on the severity of pain and tolerability. It can be taken up to 48 sprays in 24 hours maximum.|
|Tourette Syndrome||4 sprays per day|
|Diabetic neuropathic pain||4-10 sprays a day, depending on the severity of pain.|
|Pain associated with cancer and opioid use||1-10 sprays a day depending on pain levels|
|Nausea and vomiting induced by chemotherapy||3-8 sprays a day, depending on tolerability of the individual.|
What is the ideal CBD dosage?
There is no research which states a standard dose, duration or mode of intake.
The dose is unique to an individual and depends on what suits one best.
One can formulate a dose specific to one’s condition by using data from available studies and determining one’s tolerability levels.
How much CBD can you take in a day?
Note: You need to consult a doctor before going ahead with CBD for any disorders.
For preventive use: 0.5 mg-20 mg CBD per day
For therapeutic use: Varying doses may be used as some diseases require low while others may need relatively high doses.
For conditions like headache, pain, inflammation, anxiety, depression, sleep disorders, mood disorders, metabolic ailments, arthritis, IBD, weight loss, stress and nausea a medium dose of 10 mg-100 mg CBD per day can be taken.
For severe conditions like cancer, seizures, epilepsy, psychosis and schizophrenia, therapeutic doses of 50 mg-800 mg CBD per day can be taken.
The above dosages can be divided into two or three parts and taken twice or thrice daily at regular intervals.
If using CBD and THC together, combine them in a ratio of 1:1 such that the dose of CBD+THC is equal to the corresponding above-mentioned doses of CBD.
For example, if taking a preventive dose of 20 mg, combine 10 mg of CBD with 10 mg of THC.
What is the maximum dosage and duration of CBD use?
Acute use of 1500 mg CBD per day for up to 2 weeks  and Chronic use of 300 mg CBD per day for up to 3-18 weeks or 126 days has been found to be safe and well-tolerated in humans.
Nabiximols or oromucosal sprays containing equimolar ratios of CBD and THC have been found to be effective and safe for long-term use of up to 12 months.
How to start taking CBD?
Whatever CBD product one is using, check out the potency/concentration/amount of CBD contained in it.
When starting to take CBD, it is best, to begin with small doses.
The dose can be gradually increased to reach the desired dosage amounts if no significant adverse effects are noticed.
This is because different individuals have varying levels of tolerability.
One might be able to take a larger dose, while the same dose may lead to side effects in another person.
Add CBD oil to the vaporizer and inhale the fumes. CBD powder can be mixed with ethanol and vaporized.
For inhalation, it has been found that small doses of CBD (up to 4 mg) when inhaled through a vaporizer can result in up to 97.5% delivery while a high dose (of up to 200 mg ) may decrease the delivery to 40%.
This means that if one inhales 200 mg of CBD, about 80 mg is delivered through vapors.
In the case of topical application, pure CBD oil has to be diluted.
CBD-rich oil may cause irritation and allergies in some individuals.
Therefore it must always be diluted by mixing with other oils, preferably olive or coconut oils, which are well-tolerated.
Also, conduct a patch test before applying to the affected body area. In case of irritations, dilute further and check the tolerability of your skin.
When not to take CBD?
CBD can interfere with the metabolism of certain drugs. Thus, concomitant use with other medicines should be avoided.  
Precautions to be taken
If severe adverse effects are noticed, discontinue CBD use or reduce the dosage and consult with a medical professional.
CBD itself is safe, non-toxic and does not cause any serious adverse effects.
However, products containing other cannabis extracts along with CBD may cause neurobehavioral, cardiovascular, metabolic side effects and might not deliver the desired therapeutic effect. 
CBD and other cannabis extracts have immunomodulatory properties and might not be suitable for individuals with an already compromised immune system, as seen in HIV and cancer patients.
CBD has been found to interact with ant-epileptic drugs.
Always use products of good quality and reputed brands.
As with any herbal medicine, always notify your doctor prior to use, especially if suffering from a health condition.