Anxiety and sleep
Reduces anxiety: In some studies, passionflower has shown comparable effectiveness to anti-anxiety medications (like oxazepam) for generalized anxiety, and it may also reduce anxiety before medical procedures.
Aids sleep: It can help to calm the mind and body, which may shorten the time it takes to fall asleep. Some studies suggest it improves subjective sleep quality, though more research is needed on its effects on sleep duration and awakenings.
Relieves nervous unrest: Approved in Germany in 1985 as a treatment for nervous unrest, passionflower is considered a mildly effective sedative. The anxiolytic (anxiety-reducing) effect is thought to be partly due to its ability to increase the brain's levels of gamma-aminobutyric acid (GABA), a neurotransmitter that promotes relaxation. 
Menopause and ADHD
Menopause symptoms: Some research suggests that passionflower may help alleviate menopausal symptoms, including insomnia, depression, headaches, and hot flashes.
ADHD symptoms: Some emerging studies and traditional use suggest that passionflower may help manage symptoms of attention-deficit/hyperactivity disorder (ADHD), though more rigorous clinical trials are needed to confirm these findings. 
Stomach and digestive health
Soothes the stomach: Some traditional and animal studies suggest that passionflower and related species in the Passiflora family may offer gastroprotective benefits.
Addresses nervous stomach: Because of its calming effects, passionflower is also used for gastrointestinal complaints related to stress or nervousness.
Rich in fiber: The fruit of the passionflower plant, commonly known as passion fruit, is a good source of dietary fiber, which is important for digestive health and preventing constipation. 
Other traditional uses
Historically, Passiflora incarnata has also been used for other conditions, though evidence for these uses is more limited: 
Pain, including headaches and menstrual cramps
Symptoms of drug withdrawal
Muscle spasms and seizures
Cardiovascular issues like palpitations