Ginkgo leaf extract is used to treat the following conditions:

Symptoms of aging associated with Alzheimer's disease.
Improves brain functions.
Helps treat migraines.
It helps in treating asthma.
Treating anxiety: Some research has shown that taking ginkgo extract for 4 weeks can reduce symptoms of anxiety.
Vision problems in diabetics. These extracts may benefit from protecting the retina from damage and increasing blood flow.
Treating leg pain resulting from poor blood flow in the blood vessels.
It is used in some cases to relieve dizziness and balance disorders.
It is used alongside antipsychotic medications to treat schizophrenia.
Helping treat erectile dysfunction resulting from the use of depression medications.
It works as an anti-inflammatory in some cases such as arthritis and irritable bowel disease.
It helps in treating intestinal worms.
Helps relieve menstrual symptoms.