Passionflower: Clinical Use. Dosage


Passiflora extract is a popular herb for nervousness and is most often prescribed in combination with other herbs such as valerian. A 2001 double-blind, randomised controlled study involving 36 outpatients diagnosed with GAD found that Passiflora extract was as effective as oxazepam 30 mg/day over a 4-week period and better tolerated.

Commission E approved for this indication.


Currently, in vivo evidence supports the sedative activity of Passiflora when used in high doses; however, controlled studies are not available to confirm the clinical efficacy.

Passionflower: Other Uses


Traditionally, passionflower has been used to treat neuralgia, generalised seizures, hysteria and insomnia. It has also been used to treat diarrhea, dysentery and dysmenorrhoea by acting on the nervous system.


Recent tests in mice have identified significant aphrodisiac properties associated with high doses of Passiflora extract. A benzoflavone moiety may be chiefly responsible, as tests with this isolated compound were found to increase libido and fertility of males rats after 30 days’ treatment.


Passiflora incarnata was as effective as codeine phosphate in suppressing a sulfur-dioxide-induced cough in mice. Passionflower (100 mg/kg) was also able to prevent dyspnoea-related convulsions in guinea pigs with acetylcholine-induced bronchospasm.


A randomised double-blind study involving 65 subjects with opiate addiction compared the effects of clonidine and placebo with clonidine and Passiflora extract over a 14-day period. The combination treatment of clonidine and Passiflora extract showed significant superiority for alleviating the psychological symptoms associated with withdrawal; however, no differences in physical symptoms were seen.

Although no clinical studies are available for Passiflora extract, preliminary results from animal studies testing the benzoflavone moiety isolated from Passiflora has found it to be a useful adjunct during cannabis and alcohol withdrawal, reducing dependence and attenuating withdrawal symptoms.

Passionflower: Dosage Range

• Dried herb: 2 g three to four times daily.

• Infusion of dried herb: 0.25-2 g three to four times daily.

• Fluid extract (1:1) (g/mL): 2 mL three to four times daily in 150 mL of water.

• Tincture (1:5) (g/mL): 10 mL three to four times daily.