CBD Oil Interactions - What drugs should not be taken with CBD

CBD Oil Interactions: What drugs should not be taken with CBD?

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CBD Oil Interactions: What drugs should not be taken with CBD?

In recent years, many people have lived consciously towards a healthier and cleaner life. Many have opted to shift to more organic choices—from the food they consume, the products they buy, and the medicine they take. Many have also geared to trying CBD oil to act as aid with various health conditions, like easing pain, improving sleep and mood, and basically, just for overall wellness. Nowadays, you can easily get various types of CBD products from suppliers like Reakiro, ranging from CBD oil, CBD capsules, and CBD hair prays. CBD oil users must still stay wary of how CBD oils interact with other medications. So, one has to wonder, “What drugs does CBD interact well with?”

What Drugs Should Not Be Taken With CBD?

Drug-drug interactions occur when two or more drugs are co-administered to a patient [1]. CBD users must be cautious, as they may experience unexpected side effects. Take, for example, a sedative and antihistamine. If you take both medications, it can slow down your reactions and make driving a car or operating heavy machinery dangerous. It is important to discuss with your physician all the medications you take before you even think of self-medication or changing your doses. This is also crucial when you’re using or considering CBD as an enhancement to your medication. So, what drugs should not be taken with CBD?

  • CBD, or cannabidiol, is an active compound. CBD products are all the rage these days as it promises relief from a wide range of conditions — from insomnia, hot flashes, chronic pain, and many more. CBD has a lot of potential health benefits. That’s why many wonder if it can have unintended reactions with certain medications for certain ailments. Cannabidiol or CBD is a biologically active compound, so it can’t be helped if it produces adverse effects when it interacts with other compounds. Specifically, we should be cautious when mixing it with supplements, over-the-counter (OTC) prescription medications, and herbal products. Reading the labels of your current medication and doing research is the best thing to do to avoid any harmful side effects of drug-drug interaction.
  • CBD And Other Drugs. There are lists of what drugs should not be taken with CBD. The CYP450 family of enzymes metabolises cannabinoids, including CBD [2]. CBD interferes with CYP3A4, which is an important enzyme in the CYP450 family and metabolises 60% of clinically prescribed medications. If you take CBD with these medications, the body can’t work effectively to process the CBD. You may have more medication in your system than intended when your body is metabolising medication slowly. An increased level of medication in your system could exaggerate the medications’ effects and can cause more harmful effects than good.

CBD Oil and levothyroxine

Hypothyroidism is a common condition where the thyroid gland doesn’t create and release enough thyroid hormones into the bloodstream. However, when thyroid glands produce little thyroid glands, it becomes a problem. We need the thyroid as it controls energy levels and growth in a person’s body. No one wants this to happen, so levothyroxine as a medication is used. Now, on another note, a study published in 2019 suggests that CBD may indirectly improve anti-inflammatory effects and reduce the levels of pro-inflammatory cytokines[3]. Will CBD be a great alternative for levothyroxine? Well, let’s take a deeper dive into how these two medications help with hypothyroidism.

  • Levothyroxine and Hypothyroidism: levothyroxine is a prescription drug administered to treat primary, secondary, and tertiary hypothyroidism. You can take levothyroxine orally, whether it is as cannabidiol tablets or CBD liquids. Levothyroxine is effective in replacing missing thyroid hormones. However, even though levothyroxine works right away, it may take several weeks before hypothyroidism symptoms improve. Another thing is if you stop taking medication, symptoms are likely to return.
  • CBD oil and hypothyroidism: So, how about an alternative to levothyroxine instead? Not only does CBD help with headaches caused by hyperthyroidism, but it also helps manage the pain caused by inflammation. CBD stimulates the endocannabinoid system or ECS. A study published in 2015 showed that enhanced CB1 and CB2 receptors have the potential to block malignant cells from spreading in the thyroid gland[4]. These receptors have therapeutic tendencies that can inhibit tumour progression. CBD is quite promising. However, further studies are needed to see the full potential of CBD oil’s effect on the thyroid in humans. 

CBD and Heart Medications

Physicians these days are prepared with medications they can prescribe to help their patients in the battle against heart disease. These medications, if administered with the recommended dosage, can help improve a patient’s quality of life. So, if you’re asking, where does CBD come into play? Well, studies have suggested that CBD can have a protective effect on the heart because of its anti-inflammatory properties[5]. There is ongoing research into the use of purer forms of CBD for a variety of conditions like heart and circulatory diseases. Can CBD Oils contend with existing heart medications? Time to find out.

  • CBD and high blood pressure medication: Preclinical studies have shown that CBD has many cardiovascular benefits, which include the lowering of blood pressure response due to stress. In another study, with CBD’s help, there was (again) reduction of blood pressure in stressed patients[6]. Quite promising, right? However, another study done in 2011 found that CBD sometimes increased blood pressure and sometimes decrease. This is where then we draw the line. If you’re hunting for a CBD product, it’s important to consider the cannabidiol side effects when mixed with some medications, including those used for hypertension. If we may add, the best CBD product to consider for blood pressure is a CBD tincture, like the ones you can find in Reakiro, as it easily gets absorbed into the system.
  • CBD and beta-blockers: CBD alone have shown great potential in controlling or lowering high blood pressure. Beta-blockers, or beta-adrenergic blocking agents, are medications that reduce blood pressure. It blocks the effects of adrenaline and causes the heart to beat more slowly and with less force. Many patients’ heart conditions, especially high blood pressure, combine CBD and beta-blockers for high efficacy[7]. It’s been reported that patients who do so experience an effective reduction of high blood pressure or expect stabilized pressure levels throughout the day. Another reason why CBD and beta-blockers are combined is to cancel out the side effects brought about by taking beta-blockers.

CBD Oil and Antibiotics and Antibacterial

CBD may be one of the promising ways to fight off infection. There’s evidence that CBD possesses antimicrobial properties[8]. And what’s more incredible about this is, CBD may even be effective against bacteria that have already been resistant to the traditional antibiotics (e.g., penicillin). But is CBD powerful enough to have that antibiotics benefit?

  • CBD oil and antibiotics both fight infection. However, CBD oil and antibiotics use different ways to achieve this goal. Antibiotics wipe out elements of bacterial cells, including good bacteria that help with gut health. On the other hand, CBD has demonstrated antimicrobial properties. Studies have concluded that CBD is effective against treatment-resistant bacteria. If you combine CBD oil and antibiotics in the right dosage, you will have a strong defence against bacteria-caused diseases.
  • How much CBD Oil to kill bacteria: High levels of CBD have no power to kill bacteria unless delivered in a compatible vehicle. However, in a recent study discussing the antimicrobial potential of cannabidiol, CBD represents the prototypical member of an existing structural class of antibiotics. A clinical trial is also on its way to check the effectiveness of CBD’s antimicrobial activity as a topical therapy for nasal decolonization. Amazing, indeed. Because of CBD’s safety profile, it’s becoming a new and attractive form of antibacterial medication. Again, we patiently wait as more research needs to be done to pinpoint if there are specific pathways targeted by CBD.
  • CBD as Antibacterial: Will it work? We need to see further studies about CBD to know exactly what mechanism handles CBD’s high efficacy as an antibacterial agent. In addition, no existing study recommended combining CBD with antibiotics and antibacterial drugs. It’s important to establish the right CBD oil-antibiotic dosage and routine to avoid negative interactions between the two substances. So, if you ask, will CBD work? We still have no answer, as we wait for more CBD research to unfold in front of us. It’s safe to say we lobby behind CBD’s potential benefits and existing thousand anecdotal pieces of evidence with caution.

CBD Side Effects

CBD is a natural compound and is generally considered very safe with tolerant compounds. One cannabidiol side effect is its interaction with the P-450 enzyme system. It inhibits the cytochrome P-450 enzyme system, an essential pathway that processes and breaks down medication into smaller substances[9]. The metabolic process of the P-450 enzyme system is slowed down when CBD interacts with other medications. So, what drugs should not be taken with CBD? For a clearer picture, here are some specific examples of what medications does CBD interferes with.

  • Interaction between CBD oil and levothyroxine: As mentioned earlier, both CBD oil and levothyroxine can help with hypothyroidism. If spaced out between the use of CBD oil and levothyroxine properly, there may be minimal or no effect at all. However, if CBD oil and levothyroxine are co-administered, anxiety, mild nausea, and even a new condition called hyperthyroidism can appear. It was discovered that if a patient takes both CBD oil and levothyroxine, the body will compile more thyroxines before the body even has time to metabolise them, hence hyperthyroidism[10]. If you’re adamant about taking both medications, consulting with your doctor to establish the right routine for both compounds is highly recommended.
  • Interaction between CBD and high blood pressure medication: So, does CBD interfere with blood pressure medication? Results from a published journal in the Cannabis and Cannabinoid Research Journal suggest that combining CBD and high blood pressure medication has the potential to alter the blood concentration of either substance[11]. This can lower a person’s blood pressure to unhealthy levels. We recommend speaking with a medical expert before adding CBD as an add-on medication for hypertension. The doctor may likely suggest lowering the dosage of your prescription before incorporating CBD oil into the daily regimen of the patient. As for side effects, further research needs to be done to determine CBD’s potential benefits and even impairment in cardiovascular conditions.
  • Interaction between CBD and beta-blockers: When CBD oil interacts with beta-blockers, it can cause a lowering in your blood pressure levels. This happens because CBD oil amplifies the effects of beta-blockers. This is great for patients who experience heart problems. However, in extreme cases, you could faint or even be in a state of shock when your blood pressure drops too low. If you’re eager to use CBD and beta-blockers or replace your beta-blockers with CBD because of its cost-effectivity, ask your physician or cardiologist first.
  • Interaction between CBD and antibiotics: CBD oil may impede the liver’s ability to metabolise certain antibiotics[12]. This can cause higher concentrations of antibiotics to circulate in the bloodstream, which can cause negative side effects[13]. These side effects may include diarrhoea, headaches, mood swings, nausea, stomach pain, and weakness. The Indiana University Department of Medicine released a list of what drugs should not be taken with CBD, and this list includes antibiotics like amoxicillin, doxycycline, cephalexin, ciprofloxacin, amoxicillin-clavulanate, levofloxacin, and many more[14]. Let’s not dismiss the fact that not every antibiotic will react negatively to CBD. As mentioned before, it can even enhance the effects of antibiotics.


CBD is relatively safe but it can cause adverse effects when mixed with other medications. Available CBD information has pointed out that CBD and heart medication, CBD and antibiotics, and CBD and beta-blockers are not desirable drug-drug interactions. To make your life easy, there is existing research about the mix-and-match activities with CBD, so it is best to consult that first before deciding to take CBD as an alternative for alleviating the symptoms you’re experiencing. It’s also best to seek an opinion from a medical professional to help you learn about potential CBD side effects when co-administering with supplements or prescription medication. Remember, do not assume that because something is natural, it’s 100% safe.


  1. CBD and other medications: Proceed with caution
  2. Cannabinoids and Cytochrome P450 Interactions
  3. Antioxidative and Anti-Inflammatory Properties of Cannabidiol
  4. Clinical Significance of Cannabinoid Receptors CB1 and CB2 Expression in Human Malignant and Benign Thyroid Lesions
  5. Does Cannabidiol Protect Against Adverse Psychological Effects of THC?
  6. Vasodilatory effects of cannabidiol in human pulmonary and rat small mesenteric arteries: modification by hypertension and the potential pharmacological opportunities
  7. A single dose of cannabidiol reduces blood pressure in healthy volunteers in a randomized crossover study
  8. The antimicrobial potential of cannabidiol
  9. The Effect of Cytochrome P450 Metabolism on Drug Response, Interactions, and Adverse Effects
  10. CBD For Thyroid Health: Can It Help As Alternative Medication?
  11. A single dose of cannabidiol reduces blood pressure in healthy volunteers in a randomized crossover study
  12. CBD Oil and Antibiotics: Is It More Effective to Take Them Together?
  13. Prevalence and clinical characteristics of antibiotics associated drug induced liver injury
  14. CBD Drug Interactions – Mixing Cannabidiol and Medications
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