When you are taking several different medications, you need to know how drugs interact. For those on the prescription drug Wellbutrin for depression, anxiety, or smoking cessation and less frequently also on diphenhydramine which is an antihistamine that is available over the counter. It is vital to know if can you take Wellbutrin and diphenhydramine together? The two drugs are both used frequently, but it doesn’t necessarily mean that one should be taken with the other. In this blog, we’ll dive deeply into the potential risks, side effects, and essential things to consider before using Wellbutrin and diphenhydramine simultaneously.

What Is Wellbutrin (Bupropion)?

Wellbutrin works through the central nervous system, affecting the brain’s balance of neurotransmitters like dopamine and norepinephrine. It is categorized as atypical antidepressants and is more likely to activate one than most other antidepressants.
Wellbutrin is a prescription medication commonly used to treat conditions like:

• Depression (particularly major depressive disorder),
• Anxiety (though it’s more commonly prescribed for depression),
• Seasonal affective disorder (SAD),
• Smoking cessation (under the brand name Zyban).

An important aspect is that Wellbutrin may lower the seizure threshold, making it more likely for someone to experience a seizure. This becomes an essential consideration when co-administering Wellbutrin with specific drugs or agents.

What Is Diphenhydramine?

It works by blocking histamine receptors in the body, which reduces symptoms like sneezing, runny nose, and itching. One of diphenhydramine’s most common side effects is drowsiness, so it is used to enhance sleep.
Diphenhydramine is a class of antihistamines usually used for the following reasons:

• Allergy symptoms,
• Symptoms of a cold,
• Motion sickness, and
• An agent for aiding sleep as it has some sedating effect.

While diphenhydramine can be purchased over the counter and is considered safe as long as it is used for the prescribed amount of time, it can cause various side effects, such as dry mouth, blurred vision, constipation, and urinary retention. These may be exacerbated when combined with other medications, especially CNS-active drugs.

Can You Take Wellbutrin and Diphenhydramine Together?

In most cases, there is no strict contraindication for using Wellbutrin and diphenhydramine together. However, several factors need to be considered when combining these two medications.

Seizure Risk

The primary concern of taking Wellbutrin is that it lowers the seizure threshold. It makes a patient prone to seizures on Wellbutrin, more so when they are under high doses or if this drug is used with substances that affect the nervous system.
Though it is not thought actually to lower the seizure threshold, there is a bit of concern when combining CNS-active drugs, particularly in those with a history of seizures or those at risk for them. It might slightly increase the seizure risk when Wellbutrin is combined with sedating drugs such as diphenhydramine, mainly if the latter is used in higher-than-recommended doses.

CNS Effects (Drowsiness, Dizziness, Confusion)

Diphenhydramine is a sedative, and the most common side effect that occurs with this drug is drowsiness. Wellbutrin itself has stimulant-like effects. So, this will result in a contradictory interaction. You might become sleepier or dizzier than usual, leading to difficulty concentrating or being able to do anything mentally stimulating.
Some individuals may experience confusion or poor coordination, especially if taken in conjunction with one another. The impairment can be enhanced if given to older individuals or persons with some previous cognitive dysfunction.

Anticholinergic Effect

Diphenhydramine is an anticholinergic. This means it can prevent acetylcholine from acting, thus affecting movement of muscles and cognitive ability. When combined with CNS-active drugs such as Wellbutrin, side effects that are potentiated by these anticholinergic effects may occur.
Side effects of anticholinergic medications include the following:

• Dry mouth
• Blurred vision
• Urinary retention
• Constipation

These may be exacerbated by combining these medications with others that affect neurotransmitter activity, like Wellbutrin.

What Should You Do Before Taking These Medications Together?

If you ever consider taking Wellbutrin and diphenhydramine together, it is high time you consult your physician. Here are a couple of steps to take before these medications are combined:

Talk to Your Doctor

Always consult your doctor or pharmacist about starting new medicines; you already use Wellbutrin. They would diagnose your specific health case and how much Wellbutrin you take. They could also diagnose medications you are on now, which may influence the chances.

Familiarize Yourself with Your Medical History

If you have a history of seizures that are more than 65 years old or have other neurological conditions, you may be at risk for complications when you are on a combination of such medications. Your doctor may have more advice on that basis.

Follow Dosage Instructions

If your doctor is fine with the prescription of Wellbutrin and diphenhydramine together, it’s essential to adhere to the prescription. For example, diphenhydramine should not be taken in high dosages since this can lead to increased side effects, such as drowsiness and confusion. Never take more than is recommended.

Pharmacogenomic Testing for Wellbutrin and Diphenhydramine Interactions

Pharmacogenomic, or PGx, testing is essential in customizing medication regimens to reflect what doctors now know. Genetic makeup determines how well drugs work on any particular person. PGx testing of RPh Labs might be crucial when planning for the simultaneous prescription of diphenhydramine, Wellbutrin, and bupropion. For example, variations in CYP2B6 like that between Wellbutrin and CYP2D6 like that between diphenhydramine make the body metabolize those drugs differently, thereby having a greater chance of a side effect such as convulsions, drowsiness, or confusion. PGx testing shows where the metabolism of those drugs lies; therefore, PGx helps in developing drug treatment plans that have minimized adverse interactions between drugs. Consequently, it makes the drugs safer and more effective once administered in multitherapy.

Conclusion

In summary, there is no absolute contraindication to taking Wellbutrin (bupropion) and diphenhydramine together. Still, the risks include increased seizure risk, CNS side effects such as drowsiness and confusion, and anticholinergic effects. PGx testing can help know how your body processes the medicines, thereby reducing the risk of adverse interactions. Ideally, seeking advice from a health professional before taking such drugs in combination is always recommended, particularly when the patient has some underlying diseases or is taking other medicines. This way, all such factors are carefully thought through, and professional advice is followed to make a sound decision for your safety.

FAQs

References

https://medlineplus.gov/druginfo/meds/a682539.html#:~:text=Diphenhydramine
https://medlineplus.gov/druginfo/meds/a695033.html
https://go.drugbank.com/drugs/DB01075