What happens when you take clonazepam with passionflower?
Clonazepam (Klonopin) is a long-acting benzodiazepine used for anxiety, panic disorder, and certain seizure conditions. Passionflower (Passiflora incarnata) is a flowering plant traditionally taken for anxiety and sleep. Both appear to work on the same target in the brain, so taking them together can add to each other's sedating effect.
- Clonazepam boosts GABA. Benzodiazepines enhance the action of GABA, the brain's main calming (inhibitory) neurotransmitter, at the GABA-A receptor. That is what produces their anti-anxiety and sedative effects.
- Passionflower acts on the same system. Laboratory studies suggest Passiflora incarnata constituents influence the GABA system, and herbal references note that passionflower may increase the sedative effect of benzodiazepines by enhancing their binding to GABA receptors.
- The effects can stack. Because both are pulling in the same direction, the practical result is additive central nervous system depression: more drowsiness, slower thinking, and reduced coordination.
- The added effect is hard to predict. Passionflower products vary widely in potency, and the human evidence for this specific combination is limited, so the size of any extra sedation is uncertain from person to person.
Why is this important?
Passionflower is sold over the counter as a gentle, natural calming aid, so many people on clonazepam add it without telling their prescriber. The "natural and traditional" framing makes it easy to forget that it acts on the same receptor system the prescription is already targeting.
The main concern is excess sedation, especially when other sedating substances are also in the mix. Alcohol, opioids, sedating antihistamines like diphenhydramine, other benzodiazepines, and Z-drugs all push in the same direction. Clonazepam's long half-life means levels build up with daily dosing, so an added sedating herb can occasionally tip a steady state into impairment that is felt the next morning rather than just at bedtime.
Older adults warrant extra care. Benzodiazepine clearance slows with age and balance is more easily affected, so layering a sedating herb on chronic clonazepam can contribute to unsteadiness and fall risk.
It is worth keeping perspective. The evidence here is suggestive, not alarming: the mechanism is plausible and supported by lab data, and there is a published case report of additive effects (tremor, dizziness, fatigue) in a person who combined a benzodiazepine with passionflower and valerian. That is enough to justify caution, not panic.
What should you do?
If you take clonazepam regularly, the simplest safe approach is to avoid passionflower. Here is a practical way to think about it.
Before making any change: Do not stop clonazepam on your own. Benzodiazepine withdrawal can be dangerous and must be tapered with clinician supervision. If you have already been taking both, tell your prescriber or pharmacist so they can advise you. If you are interested in passionflower as part of a benzodiazepine taper, that is something to do under clinician supervision, not as a self-directed experiment.
Every day, while you are on clonazepam: Skip stand-alone passionflower capsules, tinctures, and teas, and read multi-herb stress and sleep formulas carefully for Passiflora. Be especially cautious about combining clonazepam with alcohol or other sedatives, and avoid driving or operating machinery if you feel unusually drowsy.
After any change: Watch for excess drowsiness, confusion, balance problems, slowed breathing, or trouble being woken. If any of these occur, contact your prescriber and avoid activities that require alertness. For everyday anxiety and sleep support that does not interact with your medication, the strongest non-drug evidence supports cognitive behavioral therapy, regular aerobic exercise, mindfulness, and good sleep hygiene.
Which specific products are affected?
Clonazepam is sold under the brand name Klonopin and as generic tablets and orally disintegrating tablets. The caution applies to all of them.
For passionflower, the ingredient names to look for include passionflower, passion flower, Passiflora incarnata, passion vine, and standardized passionflower extract. It appears in single-herb capsules, tinctures, glycerites, and teas, and is a common ingredient in multi-herb anxiety and sleep blends alongside valerian, lemon balm, chamomile, hops, kava, magnesium, and L-theanine. Multi-ingredient nighttime products are particularly likely to combine several mild sedatives whose effects compound, so passionflower hiding in a stress or calm blend is easy to miss if you only read the front of the bottle.
The science behind it
The evidence for this pairing is consistent in direction but limited in strength, so the caution rests mostly on a plausible shared mechanism rather than large clinical trials.
- Memorial Sloan Kettering's About Herbs reference states that passionflower may increase the sedative effects of benzodiazepines by increasing their binding activity at GABA receptors, while noting that the clinical relevance is not established (mskcc.org).
- Appel K, et al. Modulation of the GABA system by Passiflora incarnata L. Phytother Res. 2011 — an in vitro study showing the extract affects GABA uptake and binding, supporting a biologically plausible mechanism (PMID 21089181).
- A published case report (Lorazepam/passiflora/valerian root interaction, Reactions Weekly 2010;1291:24) describes a patient on the benzodiazepine lorazepam who added Passiflora incarnata plus valerian and developed tremor, dizziness, and muscular fatigue, consistent with an additive GABAergic effect (link.springer.com).
- Consumer drug references such as the RxList/WebMD passionflower monograph advise that taking passionflower with CNS-depressant medications, including clonazepam, may cause excessive sleepiness (rxlist.com).
Taken together, the mechanism is well supported but the direct human evidence for clonazepam specifically is thin, which is why this is rated a moderate caution rather than a strong warning.
Frequently Asked Questions
Is it dangerous to take passionflower with clonazepam?
It is best treated as a caution, not a proven danger. The likely effect is extra drowsiness rather than a severe reaction, but because both act on the same brain system and passionflower products vary in strength, the simplest safe choice is to avoid the combination and check with your prescriber.
Can I have a cup of passionflower tea while on clonazepam?
A single weak tea is unlikely to cause a dramatic problem, but it works on the same pathway as your medication, so it is reasonable to skip it. If you want to use it, mention it to your doctor or pharmacist first and avoid driving if you feel drowsy.
I have been taking both. Should I stop my clonazepam?
No — do not stop clonazepam on your own. Benzodiazepine withdrawal can be dangerous and needs a supervised taper. Stop the passionflower instead and let your prescriber know so they can review your situation.
What symptoms should make me concerned?
Excess drowsiness, confusion, poor balance, slowed breathing, or being hard to wake. If any of these happen, contact your prescriber, avoid driving, and seek urgent care for severe breathing problems or unresponsiveness.
Why do some studies use passionflower to help people come off benzodiazepines?
There is research on standardized passionflower extracts easing benzodiazepine withdrawal, but those studies were done under clinician oversight as part of a tapering protocol. That is different from layering passionflower onto a stable benzodiazepine dose at home.
Are other calming herbs a safer choice?
Many calming herbs (valerian, kava, hops) also have sedative effects and can stack the same way. Any herb you are considering alongside clonazepam is worth running past your doctor or pharmacist first.
Key takeaways
- Clonazepam and passionflower both act on the brain's GABA system, so combining them can add to sedation.
- The most likely effect is extra drowsiness; the human evidence is limited and suggestive, so this is a moderate caution, not a severe risk.
- If you take clonazepam, the safest choice is to avoid passionflower supplements, teas, and multi-herb sleep blends.
- Never stop clonazepam abruptly — benzodiazepine withdrawal requires a supervised taper.
- Review any calming herb with your doctor or pharmacist before adding it.