Cannabis Interacting with Other Medications: What You Need to Know

As more patients turn to cannabis for relief, it’s important to understand how it interacts with other medications. Cannabis can influence the way certain drugs work in the body. These medications can potentially enhance or reduce the effects of cannabis.

If you’re taking regular medications and planning to add medical marijuana to your regimen, consult with a medical marijuana doctor first. Apply for a medical marijuana card to get started.

The Cytochrome P450 Enzyme System

The cytochrome P450 (CYP450) enzyme system is responsible for metabolizing many medications in the liver. Cannabis can either slow down or speed up how these enzymes work. It affects how quickly drugs are broken down and absorbed into the bloodstream.

CBD can inhibit CYP450 enzymes, slowing the breakdown of certain drugs and increasing their concentration in the bloodstream. This can lead to stronger effects and an increased risk of side effects.

THC can induce CYP450 enzymes, causing some medications to break down faster than normal, potentially reducing their effectiveness.

The extent of these interactions depends on the specific medication, dosage, and how a patient’s body metabolizes cannabinoids.

Types of Drug Interactions with Cannabis

Inhibitory Interactions

CBD slows the metabolism of certain drugs, leading to higher concentrations in the bloodstream. This can increase the potency of medications such as blood thinners and antidepressants.

Inductive Interactions

THC can speed up the breakdown of some drugs, reducing their effectiveness. This can make painkillers and immunosuppressants less effective at managing symptoms.

Additive Effects

Cannabis may amplify the effects of medications that cause drowsiness, sedation, or changes in blood pressure. It can increase the likelihood of side effects when combined with anti-anxiety drugs like Zoloft.

Medications Commonly Affected by Cannabis

Using cannabis with the medications below may increase side effects such as dizziness, drowsiness, confusion, and difficulty concentrating. Some elderly or older adults may also experience impaired thinking, judgment, and motor coordination.

Avoid or limit alcohol use while taking these medications. Refrain from activities that require full mental alertness, such as driving or operating heavy machinery, until you understand how these medications affect you.

If you have concerns, speak with your doctor. Talk to your healthcare provider about all medications, including vitamins and herbal supplements. Do not stop taking any medication without consulting your doctor first.

• Abilify (aripiprazole)
• Alfentanil
• Ativan (lorazepam)
• Benadryl (diphenhydramine)
• Brexanolone
• Buprenorphine
• Butorphanol
• Cymbalta (duloxetine)
• Flexeril (cyclobenzaprine)
• Klonopin (clonazepam)
• Lamictal (lamotrigine)
• Lexapro (escitalopram)
• Lyrica (pregabalin)
• Oxycodone
• Prozac (fluoxetine)
• Seroquel (quetiapine)
• Valium (diazepam)
• Xanax (alprazolam)
• Zoloft (sertraline)
• Zyrtec (cetirizine)

You can check the entire list here.

Risks of Combining Cannabis with Medicines

Increased Side Effects

Using cannabis with certain medications can increase the risk of side effects like dizziness, confusion, excessive sedation, and impaired coordination.

Reduced Medication Effectiveness

Some drugs may be broken down too quickly when used with cannabis. This lessens their ability to provide symptom relief.

Potential for Overdose

Medications with narrow therapeutic windows, like blood thinners or immunosuppressants, may become too potent when combined with cannabis, increasing the risk of serious side effects.

CBD vs. THC: Differences in Drug Interactions

• CBD is more likely to cause drug interactions because it inhibits the liver enzymes that metabolize many medications.
• THC is less likely to interfere with drug metabolism but can enhance sedation and alter heart rate when combined with certain drugs.
• CBD may complement some medications by reducing the need for higher doses of opioids or other painkillers.

Understanding these differences can help patients and healthcare providers make informed decisions about cannabis use alongside prescription medications.

Factors That Influence Cannabis-Medication Interactions

• Higher doses of cannabis increase the likelihood of interactions.
• Inhaled cannabis takes effect quickly. Edibles and tinctures have delayed onset but longer-lasting effects and can lead to unexpected interactions.
• Regular use can impact how medications are metabolized over time.
• A patient’s age, weight, metabolism, and liver function can influence how cannabis interacts with medications.
• Full-spectrum CBD products contain additional cannabinoids and terpenes that may influence drug interactions differently than CBD isolates.

How to Minimize Risks

• Before combining cannabis with prescription medications, consult your doctor. Inform them about any medication or supplements you’re taking.
• Begin with a small amount of cannabis and monitor their response before adjusting the dosage.
• Watch for changes in symptoms, drowsiness, dizziness, or unexpected medication effects.

Consult a Medical Marijuana Doctor

Consulting a medical marijuana doctor can help determine the right dosage and product while avoiding potential risks.

Talk to a medical marijuana doctor by applying for a medical cannabis card at TeleLeaf. Our experienced and knowledgeable cannabis physicians will evaluate your condition(s), answer your questions, and advise you on treatment—all from the comfort of your home.