Why Drug Interactions Matter With Viloxazine

Viloxazine (brand name Qelbree) is a non-stimulant ADHD medication that affects brain chemicals like norepinephrine and serotonin. Because of how it works in the body, it can interact with certain other medications — sometimes in dangerous ways.

Knowing about these interactions before you start Viloxazine can help keep you safe. Always tell your doctor about every medication, supplement, and over-the-counter product you're taking.

For background on how Viloxazine works, see Viloxazine mechanism of action explained.

The Most Dangerous Interaction: MAO Inhibitors

The most serious drug interaction with Viloxazine involves monoamine oxidase inhibitors (MAOIs). These include medications like:

• Phenelzine (Nardil)
• Tranylcypromine (Parnate)
• Isocarboxazid (Marplan)
• Selegiline (Emsam)

You should never take Viloxazine if you are currently taking an MAOI or have taken one within the past 14 days. Combining these medications can cause a dangerous spike in blood pressure and other life-threatening reactions.

If you're switching from an MAOI to Viloxazine (or vice versa), your doctor will have you wait at least 14 days between medications.

CYP1A2 Interactions: A Key Concern

Viloxazine is a CYP1A2 inhibitor. CYP1A2 is a liver enzyme that helps your body break down certain medications. When Viloxazine blocks this enzyme, it can cause other drugs processed by CYP1A2 to build up to higher levels in your blood — potentially increasing side effects or toxicity.

Medications that are sensitive CYP1A2 substrates include:

• Duloxetine (Cymbalta) — An antidepressant commonly used for depression and anxiety
• Alosetron (Lotronex) — Used for irritable bowel syndrome
• Theophylline — Used for asthma and other breathing problems
• Tizanidine (Zanaflex) — A muscle relaxant

If you take any of these medications, your doctor may need to adjust the dose or choose an alternative. Do not start or stop any CYP1A2 substrate without discussing it with your doctor.

Serotonergic Drugs: Risk of Serotonin Syndrome

Because Viloxazine modulates serotonin activity, taking it with other drugs that increase serotonin can raise the risk of a condition called serotonin syndrome. This is a rare but potentially life-threatening condition.

Symptoms of serotonin syndrome include:

• Agitation and restlessness
• Rapid heartbeat
• High blood pressure
• Dilated pupils
• Muscle twitching or rigidity
• High body temperature
• Diarrhea

Drugs that increase serotonin include:

• SSRIs — Fluoxetine (Prozac), Sertraline (Zoloft), Escitalopram (Lexapro)
• SNRIs — Venlafaxine (Effexor), Duloxetine (Cymbalta)
• Triptans — Used for migraines (e.g., Sumatriptan)
• Tramadol — A pain medication
• St. John's Wort — An herbal supplement

If you take any serotonergic medication, your doctor needs to weigh the risks and benefits carefully. Seek emergency medical help if you develop symptoms of serotonin syndrome.

Drugs That Lower the Seizure Threshold

Viloxazine may interact with other medications that lower the seizure threshold. If you take any of the following, tell your doctor:

• Certain antipsychotics
• Bupropion (Wellbutrin)
• Tramadol
• Certain antibiotics (e.g., fluoroquinolones)

Your doctor will evaluate your overall risk and determine if Viloxazine is safe for you.

Alcohol and Viloxazine

Alcohol can increase the central nervous system (CNS) depressant effects of Viloxazine, making side effects like drowsiness and fatigue worse. While there is no absolute prohibition, it's best to limit or avoid alcohol while taking Viloxazine.

Talk to your doctor about what level of alcohol consumption, if any, is safe for you. For more on side effects, read Viloxazine side effects: what to expect.

Food Interactions

Good news: Viloxazine has no significant food interactions. You can take it with or without food. Taking it with food may help reduce nausea, which is a common side effect when starting treatment.

Supplements and Over-the-Counter Products

Don't forget to tell your doctor about any supplements or over-the-counter products you take. Some that could interact with Viloxazine include:

• St. John's Wort — Increases serotonin and can raise the risk of serotonin syndrome
• Melatonin — Generally considered safe, but discuss with your doctor if you experience increased drowsiness
• Caffeine — Caffeine is processed by CYP1A2. Viloxazine may slow caffeine metabolism, potentially increasing jitteriness or insomnia

What to Tell Your Doctor Before Starting Viloxazine

Before starting Viloxazine, make sure your doctor knows about:

• All prescription medications you take
• All over-the-counter drugs and supplements
• Any history of seizures
• Any history of bipolar disorder
• Liver or kidney problems
• Pregnancy or plans to become pregnant
• Breastfeeding status (Viloxazine is excreted in breast milk)

For a full overview of the medication, read What Is Viloxazine?

Getting Your Prescription

If your doctor prescribes Viloxazine, you can use MedFinder to check pharmacy stock and find it near you. Need help with the cost? Check out Viloxazine savings programs.

Bottom Line

Viloxazine has several important drug interactions to be aware of, especially with MAO inhibitors, CYP1A2 substrates, and serotonergic drugs. The best way to stay safe is to give your doctor a complete list of everything you take — including supplements and over-the-counter products — before starting Viloxazine. If you experience any unusual symptoms after starting treatment, contact your doctor right away.