Can Passion Flower Treat Anxiety?

Brenae Ashton
Brenae Ashton

Abstract:  Can passion flower treat anxiety?

Jaqueline Simpson, Brenae Ashton, Cassandra Wilson


Background:  Discovered by Spanish explorers, the Passion flower was named to symbolize the passion of Christ for its striking purple and white flowers. The tree, also called Passiflora incarnata, and is more known for the fruit it produces, the passion fruit. It is native to central and south America, and is also found in parts of south-eastern United States.


Mechanism of action:  Similarly to benzodiazepines, passion flower is thought to disrupt GABA uptake in the synapses of neurons; additionally passionflower has shown an affinity for both GABA𝛼 and GABAᵦ receptors. The result of these actions is similar to those of benzodiazepines, resulting in sedative and anti-anxiolytic effects.1


Side effects: Overall, passion flower is generally well tolerated, but can cause side effects often seen with CNS depressants like: confusion, dizziness, and sedation.1


Drug interactions: Due to its sedative effects, passion flower is thought to have an interaction with CNS depressants, causing an additive effect and increasing the likelihood of side effects.1 Passionflower is also thought to have a minor interaction with organic anion-transporting polypeptide (OATP) substrates by reducing the bioavailability of OATP2B1 and OATP1A2.1


Clinical Evidence:  One study aimed to examine the effects of dried passion flower extract in the treatment of

non-specific anxiety. 2,928 patients were enrolled in the multicentre, open-label, observational study. Patients’ anxiety was measured using the Hamilton Anxiety Rating Scale (HAM-A) at visit 1 and visit 2 to determine efficacy via a reduction in HAM-A scores. Patients were given 400 mg of passion flower extract to be taken twice daily at visit 1 until their follow-up visit 2-8 weeks later (visit 2). The results of the study showed that there was a 41% decrease in HAM-A scores at visit 2 that ranged from 25.6 (SD = 8.3) to 15.4 (SD = 7.7). It was also noted that 15.6% of participants in the general study population and 7.1% in the ITT study population were considered to be in remission at visit 2 identified by a HAM-A score ≤ 7. The author’s concluded that the dry extract of passion flower shows therapeutic evidence for the treatment of anxiety. However, despite promising results, the study had multiple limitations that included a lack of control group, randomization, blinding, and any record of compliance to treatment.1,2


Another study aimed to evaluate the efficacy of passion flower in reducing anxiety before dental procedures. A randomized, one-sided clinical trial of 63 patients with moderate, high and severe anxiety in need of periodontal work were randomly divided into 3 groups consisting of 21 participants each. Levels of anxiety were measured and averaged in each group both before and after the procedure using the Corah’s DAS-R questionnaire. The first group was administered passion flower drops (90 drops) before and after treatment. The second group was given a placebo, administered in the same manner as described previously. The third group did not receive any treatment or placebo and was considered the negative control group. Results showed that anxiety levels in each group dropped from 12.09 to 8.47, 12.00 to 10.52, and 11.66 to 11.23 for each group, respectively. The authors of the study concluded that administration of passion flower as a premedication is to be considered very effective in reducing overall anxiety. Since this is the first study of its kind, additional research and studies must be conducted in order to accurately consider passion flower as an anxiolytic remedy.3


Conclusion:  Passion Flower uses vary from treating anxiety, to diabetes, to cough. However, it is not recommended for treatment of any disease due to lack of quality studies.1











  1. Natural Medicines Comprehensive Database.,-herbs-supplements/professional.aspx?productid=871
  2. Ansseau M, Seidel L, Crosset A, Dierckxsens Y, Albert A. A dry extract of Passiflora incarnata L. (Sedanxio) as first intention treatment of patients consulting for anxiety problems in general practice. Acta Psychiatrica Belgica 2012;112(3):5-11.
  3. com.
  4. Kaviani N, Tavakoli M, Tabanmehr M, Havaei R. The efficacy of passiflora incarnata linnaeus in reducing dental anxiety in patients undergoing periodontal treatment. J Dent (Shiraz). 2013 Jun;14(2):68-72.
  5. National Center for Complementary and Integrative Health.








Recommend0 recommendationsPublished in College of Pharmacy, Virtual Poster Session Spring 2021


  1. Nice colors! In the first study were you able to calculate number needed to treat? In the second study how does the dose used compare to that in the first study. What do you think of the study design in the second study? How do doses in the studies compare to what is stated in Natural Medicines? Would you recommend its use?

    1. According to the Natural Medicines website, most commercial products containing passion flower contain 250-900 mg per dose. The first study evaluated patients initially taking 2 capsules of 200 mg twice daily, for a total of 800 mg per day to treat generalized anxiety. The second study used passion flower in the dosage form of drops instead of capsules, making it difficult to compare the 2 studies in terms of dosing. According to the manufacturer’s website of the drops used in the study, 100 mL of the drops contains 11-15 mg of active ingredient. The patients in the second study were required to take 20 drops the night prior to and morning of dental treatment to reduce anxiety.
      As far as study design for the second study goes, I found it very effective to have both a placebo and a negative control group. Comparing the results on the graph provided on the poster showed that there was not much of a “placebo effect” in group 2, and that passion flower proved to be the most effective out of all options from the study. It would be interesting to see how it compared to pharmaceutical anxiolytics.
      For recommending the product, I do not see too much harm in this product, with the common side effects being mild sedation, dizziness, and hypersensitivity. However, I would encourage patients to look into other options in order to effectively treat their anxiety since there is much more research that needs to be done.

    2. Hi Dr. Shane-McWhorter! Unfortunately, I was unable to access the supplementary index in the first study to obtain the actual number of patients that were considered to be in remission at visit 2 (the study only reported a percentage of patients) and with a lack of placebo/control group, it was difficult to calculate a NNT. With that being said, I would have a hard time solely recommending the use of passion flower based on this study due to its limitations.

  2. Very interesting topic and awesome job on the poster! Do you think that passion flower could potentially have superiority over traditional anxiolytics? If so, in what ways?

    1. Hey Gisoo! I think that the few studies we found show promising results when it comes to using passion flower as an anxiolytic. One benefit of using this natural product could be that we reduce the amount of benzodiazepines that are prescribed which also replace some side effects that go along with taking benzos like less sedation and memory loss. Decreasing the use of a controlled substance and replacing it with what could be a non-addictive treatment would also be a win. With that being said, studies on passion flower lack critical data like large human studies and studies that include a placebo or control group. In order for passion flower to even be considered clinically we would have to make large strides to prove the superiority over traditional anxiolytics.

  3. Very interesting! I am curious though, is there any specific types of anxiety that passion flower is used for?

    1. The majority of the studies that have been done address mild to moderate non-specific anxiety. I did look into generalized anxiety but there were very few studies and most of them only used animal subjects.

  4. I like the color in your poster! I have never heard of this product before. I found it interesting that is was named by Spanish missionaries in the 15th century. Where did you get the idea for this poster?

    1. Hey Jared! We knew that we wanted to look at anxiety as the topic for our poster so with a quick google search we found that this has been a topic of discussion by multiple people and we were able to find a few studies to further base our poster off of.

    2. Hi Jared, it is also the blossom for the passion fruit, which is something I see everyday in the supermarket, and thought it would be interesting!

  5. Your poster looks great! I noticed your dosing said to use passion flower along with sertraline. Did you find studies that compared sertraline alone with sertraline and passion flower?

    1. Hi Jennie, I found this article by Mandana Nojoumi et al. at Iran J Psychiatry from 2016 who performed a double-blind placebo controlled study looking at passion flower as an add on to sertraline vs sertaline alone. The conclusion from this study was that passion flower could be a useful add on, but more studies would need to be done to confirm this. I also did a google search and was able to find similar articles with similar results as to the one my Mandana Nojoumi.

  6. Hi Brenae, Jaqueline and Cassandra!
    Interesting topic involving the Passion Flower! I was not aware of all the background info you provided on this flower, all the way back to biblical times. Regarding Study 2, did the authors use any type of measurable anxiety tool? (Study 1 used the HAM which was good to see.) Also, what is the labeling of the x and y axis in Study 2 graph? Poster is well organized and balanced. Thank you for sharing your expertise on this topic!

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