Why Drug Interactions Matter With Quviviq

Quviviq (Daridorexant) is metabolized primarily by an enzyme in your liver called CYP3A4. This is one of the most important drug-metabolizing enzymes in your body — and it's also affected by a long list of other medications, supplements, and even foods.

When another drug interferes with CYP3A4, it can either increase Quviviq levels in your blood (making side effects more likely and more severe) or decrease Quviviq levels (making it less effective). Some of these interactions are serious enough that certain drug combinations are completely contraindicated.

This guide covers every major interaction you need to know about, organized by risk level. Print it out or save it on your phone so you can share it with your doctor and pharmacist.

For background on how Quviviq works and why CYP3A4 matters, see: How Does Quviviq Work?

Contraindicated: Do NOT Take With Quviviq

The following medications should never be taken with Quviviq. The combination significantly increases Daridorexant levels in your blood, raising the risk of serious side effects including excessive sedation, complex sleep behaviors, and next-day impairment.

Strong CYP3A4 Inhibitors

These drugs block the CYP3A4 enzyme, preventing your liver from breaking down Quviviq properly. The result: Quviviq stays in your system much longer and at higher concentrations than intended.

• Ketoconazole (Nizoral) — antifungal medication
• Itraconazole (Sporanox) — antifungal medication
• Clarithromycin (Biaxin) — antibiotic
• Ritonavir (Norvir) and other HIV protease inhibitors — including combinations like Paxlovid (nirmatrelvir/ritonavir)
• Nefazodone — antidepressant
• Cobicistat (Tybost) — HIV medication booster

What to do: If you're prescribed any of these medications, your doctor should choose a different sleep medication. Do not take Quviviq with any strong CYP3A4 inhibitor.

Important note about Paxlovid: If you're prescribed Paxlovid for COVID-19 treatment (which contains Ritonavir), you must stop Quviviq for the duration of Paxlovid treatment and for at least 3 days after your last dose. Talk to your doctor about temporary alternatives during that period.

Requires Dose Adjustment: Maximum 25 mg

If you take any of the following medications, your Quviviq dose should not exceed 25 mg per night. These are moderate CYP3A4 inhibitors — they slow down Quviviq metabolism, but not as severely as the strong inhibitors above.

Moderate CYP3A4 Inhibitors

• Erythromycin — antibiotic (commonly prescribed for respiratory and skin infections)
• Diltiazem (Cardizem) — calcium channel blocker for blood pressure and heart conditions
• Fluconazole (Diflucan) — antifungal (commonly prescribed for yeast infections)
• Verapamil (Calan) — calcium channel blocker for blood pressure, heart rhythm, and migraines
• Ciprofloxacin (Cipro) — antibiotic
• Aprepitant (Emend) — anti-nausea medication

What to do: Tell your doctor about these medications before starting Quviviq. If you're already on Quviviq 50 mg and start one of these drugs, your doctor needs to reduce your Quviviq dose to 25 mg.

Avoid: Reduces Quviviq's Effectiveness

The following medications and substances speed up CYP3A4 activity, causing your liver to break down Quviviq faster than normal. This reduces blood levels and may make the medication ineffective.

Strong CYP3A4 Inducers

• Rifampin (Rifadin) — antibiotic used for tuberculosis and some other infections
• Carbamazepine (Tegretol) — seizure medication and mood stabilizer
• Phenytoin (Dilantin) — seizure medication
• Phenobarbital — seizure medication and sedative
• St. John's Wort — over-the-counter herbal supplement for depression

Moderate CYP3A4 Inducers

• Efavirenz (Sustiva) — HIV medication
• Modafinil (Provigil) — wakefulness-promoting medication
• Bosentan (Tracleer) — pulmonary hypertension medication

What to do: If you take any strong CYP3A4 inducer, Quviviq may not work for you. Discuss alternative sleep medications with your doctor. Moderate inducers may partially reduce effectiveness — your doctor can monitor your response and adjust accordingly.

Important note about St. John's Wort: Many people take this supplement without realizing it's a powerful CYP3A4 inducer. If you're using St. John's Wort for mood support and want to start Quviviq, talk to your doctor about stopping the supplement first.

Use Caution: Additive CNS Depression

Quviviq is a central nervous system (CNS) depressant. Taking it with other CNS depressants increases the risk of excessive drowsiness, impaired coordination, slowed breathing, and complex sleep behaviors.

Other CNS Depressants

• Benzodiazepines — Alprazolam (Xanax), Lorazepam (Ativan), Diazepam (Valium), Clonazepam (Klonopin)
• Opioids — Oxycodone, Hydrocodone, Morphine, Tramadol, Codeine
• Other sleep medications — Zolpidem (Ambien), Eszopiclone (Lunesta), Belsomra, Dayvigo
• Sedating antihistamines — Diphenhydramine (Benadryl), Doxylamine (Unisom), Hydroxyzine
• Muscle relaxants — Cyclobenzaprine (Flexeril), Tizanidine (Zanaflex), Baclofen
• Certain antidepressants — Trazodone, Mirtazapine (Remeron), Amitriptyline, Doxepin
• Gabapentinoids — Gabapentin (Neurontin), Pregabalin (Lyrica)

What to do: Your doctor may still prescribe Quviviq with some of these medications, but they should weigh the risks carefully. Never combine CNS depressants on your own without medical guidance. Be especially cautious with opioids — the combination can affect breathing.

Alcohol: A Major Interaction

Alcohol deserves its own section because it's so commonly overlooked. Drinking alcohol while taking Quviviq:

• Increases drowsiness and sedation significantly
• Raises the risk of complex sleep behaviors
• Impairs coordination and judgment
• Can worsen depression

The recommendation is simple: do not drink alcohol on nights you take Quviviq. Even a glass of wine with dinner can amplify the medication's effects. If you drink regularly, be honest with your doctor about your alcohol consumption before starting Quviviq.

Food Interactions

One food interaction worth knowing about: high-fat meals. Taking Quviviq with or shortly after a high-fat meal delays absorption by approximately 1.3 hours. This doesn't make the drug dangerous, but it does mean:

• It takes longer to fall asleep
• Higher drug levels may persist into the morning, increasing drowsiness

Best practice: Take Quviviq on an empty stomach or at least 2 hours after eating.

Grapefruit and grapefruit juice are moderate CYP3A4 inhibitors. While small amounts are unlikely to cause problems, regularly consuming large quantities of grapefruit products while taking Quviviq could modestly increase drug levels. When in doubt, avoid grapefruit on Quviviq.

What to Tell Your Doctor Before Starting Quviviq

Before your doctor prescribes Quviviq, make sure they know about:

1. All prescription medications you currently take
2. All over-the-counter medications — including antihistamines, pain relievers, and cold medicines
3. All supplements and herbal products — especially St. John's Wort, melatonin, valerian root, and CBD
4. Your alcohol consumption — be honest about frequency and amount
5. Any history of narcolepsy — Quviviq is contraindicated
6. Depression or suicidal thoughts — Quviviq can worsen these conditions
7. Liver problems — impaired liver function can slow Quviviq metabolism

Your pharmacist is also an excellent resource. When you fill your Quviviq prescription, ask the pharmacist to do a full drug interaction check against everything else you take.

What If You Need to Start a New Medication While on Quviviq?

If a doctor prescribes a new medication while you're taking Quviviq:

• Remind them you take Quviviq (Daridorexant)
• Ask specifically about CYP3A4 interactions
• If the new drug is a strong CYP3A4 inhibitor, you'll need to stop Quviviq or switch sleep medications
• If it's a moderate CYP3A4 inhibitor, your Quviviq dose may need to drop to 25 mg

When in doubt, call your pharmacist. They can check interactions faster than most doctors and can coordinate with your prescribers if a change is needed.

Quick Reference: Interaction Summary

Bottom Line

Quviviq's reliance on the CYP3A4 enzyme for metabolism means drug interactions are a real concern — more so than with some other sleep medications. The good news is that these interactions are well-documented and manageable with proper communication between you, your doctor, and your pharmacist.

The three most important rules:

1. Never take Quviviq with a strong CYP3A4 inhibitor
2. Don't drink alcohol on nights you take Quviviq
3. Tell every doctor and pharmacist that you take Quviviq

For more about Quviviq side effects, read: Quviviq Side Effects: What to Expect. For help affording your prescription, see: How to Save Money on Quviviq.