Evidence

These uses have been tested in humans or animals.  Safety and effectiveness have not always been proven.  Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

Key to grades

A
Strong scientific evidence for this use
B
Good scientific evidence for this use
C
Unclear scientific evidence for this use
D
Fair scientific evidence against this use (it may not work)
F
Strong scientific evidence against this use (it likely does not work)

Grading rationale

Evidence gradeCondition to which grade level applies
A

Depression (mild-to-moderate)

Human research suggests that St. John's wort is more effective than placebo and equally as effective as TCAs and SSRIs in the short-term for mild-to-moderate depression. Although St. John's wort has been shown to have fewer side effects than SSRIs, it should be used with caution and guidance of a medical professional.
B

Somatoform disorders

Somatoform disorders are mental symptoms such as pain and fear that lack a physical source or reason for their existence. Early evidence shows that St. John's wort may help with somatoform disorders. Further research is needed to confirm these results.
C

Anxiety disorder

Early research has shown promising effects of St. John's wort for anxiety disorders. High quality evidence is lacking. Further research is needed to make conclusions.
C

Atopic dermatitis (eczema)

Early research of hypericum-cream had shown positive results for atopic dermatitis, or itchy and scaly rashes. Further studies are needed before a firm recommendation can be made.
C

ADHD (children)

It is unclear whether St. John's wort is an effective treatment in children with ADHD. More study is needed to confirm these findings.
C

Bone diseases

A combination product including St. John's wort improved healing for diabetic foot ulcers and bone disease. Further study of St. John's wort alone is warranted before a conclusion may be drawn.
C

Brain tumors

Early human study showed effectiveness of St. John's wort in decreasing brain tumor size. Further study is warranted before a conclusion may be drawn.
C

Depression (children)

Early research suggested effectiveness of St. John's wort for depression in children. Higher quality research is needed before a conclusion may be drawn.
C

Depressive disorder (severe)

Although human research is promising, the effectiveness of St. John's wort for severe depression is unclear. Additional well-designed research needed before a conclusion may be made.
C

Herpes

Early research shows that a combination product containing St. John's wort improved symptoms of herpes. Further research is warranted before a conclusion may be drawn.
C

Menopausal symptoms

Sufficient evidence is lacking to recommend St. John's wort for menopausal symptoms such as depressed mood and hot flashes. More research is needed.
C

Nerve pain

Early study shows that St. John's wort may help nerve pain. Further research is needed to confirm these results.
C

Obsessive-compulsive disorder (OCD)

Evidence for the use of St. John's wort in obsessive-compulsive disorder (OCD) is conflicting. Further research is needed before a conclusion may be drawn.
C

Pain (burning mouth syndrome)

It is unclear whether St. John's wort is an effective treatment for pain associated with burning mouth syndrome. More research is needed.
C

Pain relief (after surgery)

It is unclear whether St. John's wort is an effective treatment for pain after surgery. More research is needed.
C

Premenstrual syndrome (PMS)

The effectiveness of St. John's wort for PMS symptoms such as anxiety, depression, and cravings is unclear. Further studies are needed before a conclusion can be made.
C

Seasonal affective disorder (SAD)

Although early research is promising, there is insufficient evidence supporting the use St. John's wort for depression due to SAD. Further studies are needed before a conclusion can be made.
C

Skin disorders

Limited research shows the effectiveness of St. John's wort in treating various skin disorders. Further study is warranted before a conclusion may be drawn.
C

Smoking cessation

Early research shows the effectiveness of St. John's wort for smoking cessation or in helping to quit smoking. Further research is warranted before conclusions may be made.
C

Social phobia

The effectiveness of St. John's wort for social phobia is unclear. More study is needed.
C

Weight loss

Early research shows that a combination product containing St. John's wort was effective for weight loss. Further research of St. John's wort alone is needed before a conclusion may be drawn.
C

Wound healing

Limited research shows that St. John's wort improved wound healing and decreased the formation of scars. Further study is warranted before a firm conclusion may be drawn.
D

HIV

Non-human research shows anti-viral effects of St. John's wort in AIDS/HIV, but these effects in human research are lacking. There have been multiple reports of significant adverse effects and interactions with drugs used for HIV/AIDS, such as protease inhibitors (PIs) and non-nucleoside reverse transcriptase inhibitors (NNRTIs). Therefore, patients treated for HIV/AIDS should avoid St. John's wort.
D

Irritable bowel syndrome (IBS)

Human research shows a lack of effectiveness and possible harm of St. John's wort in IBS. Overall, there is a lack of quality research. Further research is required.

Uses based on tradition or theory

The below uses are based on tradition or scientific theories. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

Abdominal discomfort or irritation, alcoholism, allergies, antibacterial, anti-inflammatory, anti-malarial, antioxidant, antiviral, asthma, athletic performance enhancement, bacterial skin infections (topical), bedwetting, benzodiazepine withdrawal, bruises (topical), burns (topical), cancer, chronic ear infections, colitis, contusions, dental pain, diarrhea, diuretic (increasing urine flow), dyspepsia, Epstein-Barr virus infection, excessive menstrual bleeding, fatigue, gastroenteritis, heartburn, hemorrhoids, immune function, influenza, insomnia, joint pain, liver protection from toxins, psoriasis, rheumatism, snakebites, sprains, substance abuse, ulcers.

This evidence-based monograph was prepared by The Natural Standard Research Collaboration

www.naturalstandard.com