Modern research shows that CBD is generally safe1. But CBD does have the potential to interact with some medications. The problem also concerns how the body metabolises certain substances.
When you start CBD, it is essential to talk with your doctor about all medications and supplements you take. For CBD starters, even small things matter. Think of herbal teas, vitamins and any over-the-counter medications you use regularly or from time to time.
CBD and blood-thinning drugs
Some studies found that CBD may increase the effects of medications used for blood thinning like warfarin or drugs with a risk of blood-thinning including ibuprofen2.
CBD can increase the action/effect of these medications, and prolong their presence in the human body. As a result, taking CBD with blood-thinning drugs may increase the risk of bleeding. CBD users should keep in mind that it is safer to monitor the usage of both simultaneously by a medical professional.
CBD and sedatives
CBD interacts with receptors in the central nervous system, and it can have sedative effects like calming and wake-inducing. When combined with sedative drugs, CBD may produce an additive effect3.
But in most cases, it depends on the individual. Some CBD consumers do not experience any adverse effect after they use both simultaneously. But before combining them, it is better to know your reaction and to play safe; it is recommended to avoid taking CBD with sedatives.
CBD and anti-seizure medications
CBD is known to help in epileptic seizures4. But simultaneous usage of CBD with anti-seizure drugs can lead to specific problems.
Some studies found that CBD may interfere with the metabolism of certain anti-seizure drugs in the liver and thus leading to severe interactions.
Thought CBD might potentiate the action of epilepsy drugs, but it may also increase chances of side effects like dizziness, constipation, breathing problems and even depression5.
CBD and statins
Statins are drugs used to reduce cholesterol levels in the human body and help reduce the risk of heart diseases. Some findings show that statins interact with CBD. If a person uses both frequently, it can lead to the increased concentration of medicines causing dangerous chemical accumulation3.
CBD and muscle relaxants
Muscle relaxants, according to some findings, can also cause some interactions with CBD. Researchers classify muscle relaxants interactions with CBD as moderate. But some people experience side effects like dizziness, lack of concentration and confusion6.
CBD and antibiotics
There are little or no drug interactions between CBD and antibiotics. Some findings show that taking CBD and antibiotics like rifampin together may decrease the effect of CBD6.
CBD and other supplements
Using CBD with some sleep-inducing supplements can lead to the additive sleepy effect. It does not mean that all CBD users will feel it. But medical experts recommend avoiding combining CBD and herbs causing sleepiness when you have to perform some technical operations.
CBD can be beneficial but it can cause some unwanted interactions when you combine it with other drugs. Therefore, knowing about such interactions may help avoid complications.
- Iffland K, Grotenhermen F. An Update on Safety and Side Effects of Cannabidiol: A Review of Clinical Data and Relevant Animal Studies. Cannabis Cannabinoid Res. 2017;2(1):139-154. doi:10.1089/can.2016.0034
- Grayson L, Vines B, Nichol K, Szaflarski JP. An interaction between warfarin and cannabidiol, a case report. Epilepsy Behav Case Rep. 2017;9:10-11. doi:10.1016/j.ebcr.2017.10.001
- Brown JD, Winterstein AG. Potential Adverse Drug Events and Drug–Drug Interactions with Medical and Consumer Cannabidiol (CBD) Use. J Clin Med. 2019;8(7). doi:10.3390/jcm8070989
- Perucca E. Cannabinoids in the Treatment of Epilepsy: Hard Evidence at Last? J Epilepsy Res. 2017;7(2):61-76. doi:10.14581/jer.17012
- Szaflarski JP. How Does Cannabidiol Interact With Antiepileptic Drugs? Neurol Rev. 2017;25(1)(11). https://www.mdedge.com/neurology/epilepsyresourcecenter/article/128497/epilepsy-seizures/how-does-cannabidiol. Accessed December 7, 2019.
- Alsherbiny MA, Li CG. Medicinal Cannabis—Potential Drug Interactions. Medicines. 2018;6(1). doi:10.3390/medicines6010003