Should You Be Using Medical Marijuana With Benadryl?

Should You Be Using Medical Marijuana With Benadryl?

Many patients across the US combine medical marijuana with other prescription drugs to enhance the effectiveness of both drugs. Benadryl, known for its allergy-relieving properties and a popular antihistamine, is one such drug.

However, it is a very well-known fact that medical marijuana and Benadryl don’t mix well and the interaction between the two can bring more harm than good. Still, as soon as the allergy season is in its full bloom, people start using Benadryl including individuals having a medical marijuana card.

Considering this, CertaMD has brought you this guide today to help you better understand the dynamics of the interaction between medical marijuana and Bendaryl.

Here’s how Benadryl works

 

Benadryl is the brand name of Diphenhydramine, commonly used to relieve symptoms of allergies, motion sickness, insomnia, and even Parkinson’s disease. It works by suppressing histamine, a chemical released during allergic reactions, which also causes drowsiness, making it a known sleep aid. The medication can also help reduce tremors and muscle rigidity in people with Parkinson’s, as it blocks certain receptors in the central nervous system that are similar to histamine receptors.

While Benadryl is available over the counter, it can cause side effects such as dizziness, drowsiness, constipation, headaches, and stomachaches. Some stronger antihistamines may require a prescription, but Benadryl remains a common choice for those seeking immediate relief.

Here’s how medical marijuana works

 

Medical marijuana contains cannabinoids, which mimic your body’s natural endocannabinoids by interacting with CB1 and CB2 receptors found in the brain, central nervous system, and throughout the body. When these cannabinoids bind to these receptors, they trigger various effects that relieve pain, reduce inflammation, improve mood, sleep aid, suppress nausea, and stimulate appetite.

Additionally, cannabinoids can be particularly beneficial for individuals with movement disorders and spasticity, relieving the symptoms and improving overall comfort. These wide-ranging effects make cannabis a versatile treatment for numerous conditions. However, you need a medical marijuana card in most of the US states to legally possess and consume cannabis for medical reasons.

What happens when you take Benadryl and medical marijuana together?

 

So taking medical marijuana and Benadryl together is not a great idea as this combination can cause moderate side effects. Researchers have yet to study this interaction in-depth to understand the actual cause behind it but they all agree that it is better to avoid taking marijuana and Benadryl together.

The most common side effects of this parking include confusion, trouble in concentrating, and dizziness. Benadryl is known to cause such side effects when paired with medications for colds, sleep, blood pressure, and even antidepressants.

This also explains why it is important to discuss your medical history and commonly used medications with a doctor while applying for a medical marijuana card. Our doctors at CertaMD are trained to make suggestions that can save you from enduring such side effects and affecting your long-term health.

Which one is the obvious choice?

 

Now that you’re facing a choice between medical marijuana and Benadryl, the obvious choice is medical marijuana. Fortunately, medical marijuana can offer similar benefits as Benadryl, depending on the cannabis strain and its CBD content.

Cannabis strains that are high in Cannabinoid (CBD) content have anti-inflammatory properties which can help in relieving symptoms of seasonal allergy. Plus, CBD also improves sleep and relaxes the fight against symptoms of neurological disorders like Parkinson’s.

Final Note

 

So the answer is no, you shouldn’t be using medical marijuana with Benadryl as the possible side effects of this interaction outweigh the potential benefits. If you still want to use both, it is better to visit a certified doctor before pairing up the two.

FAQ’s

Is it safe to use medical marijuana with Benadryl?

No, combining the two can increase the risk of side effects like drowsiness, dizziness, and impaired motor function.

What are the risks of mixing Benadryl and medical marijuana?

Both substances cause drowsiness, and using them together may lead to excessive sedation or dangerous impairment.

Can I drive or operate machinery after taking both Benadryl and medical marijuana?

No, it is unsafe to drive or operate heavy machinery after using these substances due to increased drowsiness and impaired coordination. Doing something like this anyway can land you into legal trouble as well.

Will mixing Benadryl and medical marijuana worsen side effects?

Yes, combining them can intensify side effects such as dizziness, confusion, and dry mouth.

Should I consult a doctor before using medical marijuana and Benadryl together?

Yes, always consult a healthcare provider to avoid potential drug interactions and adverse effects.

Alana Seppelt

Important Medical Information & Disclaimers

Medical disclaimer

The information on this CertaMD page is provided for educational and informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

All medical marijuana evaluations and recommendations through CertaMD are performed exclusively by licensed U.S. healthcare providers using secure telemedicine technology, in accordance with applicable state laws and regulations.

Always speak with a qualified physician or other licensed healthcare professional before making decisions about your health, changing existing medications, or starting any new treatment, including medical cannabis.

Source: FDA – Cannabis Research & Drug Approval Process

Individual results and treatment response

Medical cannabis does not work the same way for every patient. Symptom relief can depend on factors such as the type of product (THC/CBD ratio, route of administration), dose, frequency of use, underlying medical conditions, concurrent medications, and lifestyle variables like diet, stress, and sleep.

Because response and tolerability vary, ongoing follow-up with your CertaMD provider is important to review benefits, monitor side effects, and adjust your treatment plan safely over time.

Source: NIH – Therapeutic Effects of Cannabis and Cannabinoids

Possible risks and side effects

Like any therapeutic option, medical marijuana can cause side effects. Commonly reported effects include dry mouth, dizziness, fatigue, red or irritated eyes, increased appetite, headache, and temporary problems with attention, concentration, or short-term memory.

Some patients, especially with higher-THC products, may experience anxiety, rapid heartbeat, worsened mood, or perceptual changes; in rare cases, serious effects such as psychosis, significant mood changes, heart rhythm disturbances, or cannabinoid hyperemesis syndrome (recurrent nausea and vomiting) have been reported. If you notice severe, unexpected, or persistent symptoms, stop using cannabis and contact your healthcare provider or seek urgent care.

Source: Mayo Clinic – Marijuana: Safety and Side Effects

Legal and regulatory notice

Medical marijuana programs are created and regulated at the state level, and eligibility, product access, and telemedicine rules vary by jurisdiction. Under U.S. federal law, marijuana remains a Schedule I controlled substance, and clinicians typically “recommend” or “certify” medical cannabis use rather than prescribe it in the traditional sense.

Some states require an initial in-person visit before medical cannabis certification, while others allow both initial and renewal evaluations via telehealth; CertaMD operates within the specific requirements of each state it serves.

Sources: DEA – Controlled Substances Act

Telehealth.org – Cannabis Prescribing and Telehealth

Product quality, sourcing, and safety

For your safety, use only medical cannabis products obtained from licensed, state-regulated dispensaries that perform appropriate laboratory testing for potency and contaminants. Unregulated or illicit products may contain pesticides, heavy metals, microbes, or inaccurate THC/CBD concentrations, which can increase health risks and lead to unpredictable effects.

Ask your CertaMD clinician or dispensary pharmacist about product selection, dosing, onset and duration of effects, and how to store products safely away from children and pets.

Source: FDA – What to Know About Cannabis Products

Reporting adverse events and safety concerns

If you experience serious or unexpected side effects while using medical cannabis, contact your healthcare provider immediately or seek emergency care when appropriate.

Patients and caregivers in the United States can also report adverse events and product problems to the FDA’s MedWatch program online or by phone at
1-800-FDA-1088, which helps regulators monitor safety trends and protect public health.

Source: FDA – MedWatch Safety & Adverse Event Reporting

See how much you could save with a medical card

Note that this is an estimate of savings and does not constitute a guarantee. Additional taxes in your area or recent changes in local laws may affect these rates. Please verify current regulations in your state.

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