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Moderate evidenceCan You Take Passionflower With Lexapro? Safety Guide
Can you take passionflower with Lexapro (escitalopram)? No dangerous interaction is well documented, but evidence is thin, so check with your prescriber.
Updated September 2026
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There is no well-documented dangerous interaction between passionflower and Lexapro (escitalopram), but the pair has not been properly studied together, so this is a “check first” situation rather than a clear yes. The most realistic effect is a little extra drowsiness or calm, not a severe reaction. Because both act on the nervous system and the evidence is thin, the sensible step is to ask the doctor who prescribed your escitalopram before you combine them.
If your aim is a calmer day while staying on your medication, there is a better-studied option worth raising with your prescriber, covered lower down. You can see what to check on the L-theanine page, and the anxiety guide sets it among other supports.
What passionflower does
Passionflower (Passiflora incarnata) is a traditional calming herb. Its relaxing effect is generally attributed to compounds that raise activity at GABA receptors, the brain’s main calming pathway, rather than to any strong action on serotonin. An early double-blind trial by Akhondzadeh and colleagues (2001) found passionflower comparable to a low dose of the anxiety drug oxazepam for generalised anxiety, though the study was small and short. Memorial Sloan Kettering’s About Herbs summary of passionflower reaches a similar view: mild sedative promise, modest evidence, and a note that it can add to the effect of other sedatives.
Lexapro is the brand name for escitalopram, a selective serotonin reuptake inhibitor. It raises serotonin activity to support mood and anxiety, and it is prescribed and monitored by a clinician.
The theoretical interaction
Two mechanisms are worth thinking about, and neither is a proven danger. The first is additive calm: passionflower can be mildly sedating, so on top of any drowsiness from escitalopram, or alongside other sleep aids or alcohol, you might feel more tired or foggy than usual. The second is the serotonin question. Serotonin syndrome is a real risk when serotonergic agents are stacked, and Boyer and Shannon (2005) describe how it develops. That risk is well established for combinations such as an SSRI with 5-HTP, L-tryptophan, or St John’s wort. Passionflower is not a recognised high-serotonin agent, so it does not carry the same red flag. The honest limit is that this specific pairing has not been trialled, so “no reported problem” is not the same as “proven safe”.
A better-studied calming option: L-theanine
If you want something calming while staying on escitalopram, L-theanine has more direct human evidence than passionflower. It is the amino acid found in green tea, and a randomised trial by Hidese and colleagues (2019) reported lower stress-related scores in healthy adults taking 200 mg a day, with good tolerability. It has not been formally tested with escitalopram either, so it remains a prescriber conversation, but its profile is reassuring and it is not a serotonin precursor.
What to look for in an L-theanine supplement for calm while on Lexapro
Judge these products on specifics rather than calming claims. Check the dose per capsule; most research uses 100 to 200 mg, and starting at the lower end lets you find what is enough. The Suntheanine form is the one used in much of the human research, so it is a fair marker of quality. Prefer single-ingredient products, because sedative blends stack effects you cannot separate, which matters more when you are also on medication. Look for third-party testing from NSF or USP. The L-theanine page checks these against verified specs, and the anxiety guide shows where a 200 mg Suntheanine L-theanine sits among other options. Whatever you choose, run it past your prescriber before adding it.
Cautions and the bottom line
Watch for extra drowsiness if you do use passionflower with escitalopram, and stop it if you feel over-sedated. Treat any agitation, confusion, sweating, shivering, or a fast heartbeat as a reason to seek urgent medical advice, since those can signal a serotonin problem whatever the cause. None of this replaces individual guidance.
Do not start, stop, or combine anything with your antidepressant without talking to your prescriber first. They know your full medication list and can weigh this up for you. If you are struggling with your mood, please use get help.
Sources
- Akhondzadeh S, et al. Passionflower in the treatment of generalized anxiety. J Clin Pharm Ther. 2001. PubMed
- Memorial Sloan Kettering Cancer Center. Passionflower, About Herbs. MSKCC
- Hidese S, et al. Effects of L-theanine on stress-related symptoms and cognition. Nutrients. 2019. PubMed
- Boyer EW, Shannon M. The serotonin syndrome. N Engl J Med. 2005. PubMed
This article is for general information and support, not medical advice. It does not replace care from a qualified clinician. See our disclaimer and, if you are struggling, get help. Written by Enoch C.