- Apricot vine
- Passion vine
- Fleur de la passion
For Patients & Caregivers
Passionflower may reduce anxiety, but its long-term safety and effectiveness are not known.
Passiflora incarnata is a perennial wildflower that is commonly found in the southern United States. Passionflower extract is contained in many dietary supplement products marketed as sleep aids or anxiety relievers. A handful of studies in humans support these claims, although it is still unknown whether passionflower extracts are safe and effective in the long-term. Scientists are not sure how this herb works, but have speculated that compounds in passionflower may interact with receptors in the brain that would mediate a relaxation response. Studies done in mice suggest that passionflower extracts have mild anti-inflammatory activity.
- To relieve anxiety
One small clinical trial suggested that passionflower may be as effective as oxazepam, a common drug used for treating general anxiety. In addition, another clinical trial showed that passionflower reduced anxiety in presurgical patients. However, the safety and effectiveness of its long-term use are not known.
- As a sleep aid, for insomnia
Passionflower may reduce anxiety (see above), which may help induce sleep. A small study showed benefits of passionflower in sleep quality in healthy adults.
- To treat neuralgia (nerve pain)
Passionflower may help reduce anxiety (see above), and could thereby reduce the perception of pain. However, other than this theoretical association, no scientific evidence supports the use of passionflower for nerve pain.
- Ataxia (lack of coordinated muscle activity)
- Allergic reaction
- Impaired cognitive function
- Case report: One patient experienced nausea, vomiting, decreased heart rate, and several abnormalities in heart rhythm after using a passionflower supplement. The patient recovered once the supplement was discontinued.
For Healthcare Professionals
Derived from the aerial parts of the plant, passionflower is used by patients to treat insomnia, anxiety, epilepsy, neuralgia, and withdrawal syndromes from opiates or benzodiazepines. The alkaloid components (e.g., harman, harmaline) are thought to produce monoamine oxidase inhibition, while other constituents, like maltol and gamma-pyrone derivatives, cause activation of GABA receptors (1). Theoretically, passionflower may potentiate the sedative effect of centrally acting substances (e.g., benzodiazepines, barbiturates, alcohol) (2).
A small pilot study evaluated passionflower for generalized anxiety and showed comparable efficacy to oxazepam (3), but a systematic review concluded that randomized controlled studies are needed to confirm such effects (4). In patients undergoing surgery, preoperative passionflower use reduced anxiety (5) (16). However, one study found that administration of five different Passiflora incarnata extracts to mice in their drinking water produced anxiogenic effects. Two of these extracts did show an anticonvulsant effect against pentylenetetrazol-induced seizures (6).
Consumption of a low dose of passionflower tea affected short-term benefits in sleep quality in healthy adults (17). When used concurrently, passionflower was shown to enhance the pharmocological effects of St. John’s Wort (18).
Not all passionflower extracts are standardized; therefore, dosages and activities may vary.
The activation of GABA receptors by maltol and gamma-pyrone derivatives may account for passionflower’s anxiolytic and sedative properties (11). It was also suggested that the harman alkaloids have monoamine oxidase inhibitor activity (1). Passionflower exhibits mild anti-inflammatory activity (12). An ethanolic extract of passionflower reduced carrageenan-induced edema, leukocyte migration, and granuloma formation in mice, although the effect was less than that seen with aspirin (13).
Reported: Dizziness, sedation, ataxia, allergic reaction, and impaired cognitive function (3).
Case report: Nausea, vomiting, bradycardia, and ECG changes including non-sustained ventricular tachycardia, QTc prolongation, and nonspecific ST-T wave changes. Patient recovered following discontinuation of supplement (6).