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St. John's Wort

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What other names is St. John's Wort known by?

Amber, Amber Touch-and-Heal, Barbe de Saint-Jean, Chasse-diable, Demon Chaser, Fuga Daemonum, Goatweed, Hardhay, Herbe à la Brûlure, Herbe à Mille Trous, Herbe Aux Fées, Herbe Aux Mille Vertus, Herbe Aux Piqûres, Herbe de Saint Éloi, Herbe de la Saint-Jean, Herbe du Charpentier, Herbe Percée, Hierba de San Juan, Hypereikon, Hyperici Herba, Hypericum perforatum, Klamath Weed, Millepertuis, Millepertuis Perforé, Rosin Rose, Saynt Johannes Wort, SJW, Tipton Weed.

What is St. John's Wort?

St. John's wort is a plant with yellow, star-shaped flowers and five petals that grows in Europe, North and South America, Australia, New Zealand, and Eastern Asia. The plant grows in sunny, well-drained areas. It grows to be 50-100 cm tall.

St. John's wort might cause serious interactions with some drugs. Because of this, France has banned the use of St. John's wort in products. Several other countries, including Japan, the United Kingdom, and Canada are in the process of updating warning labels on St. John's wort products.

St. John's wort is most commonly used for depression and conditions that sometimes go along with depression such as anxiety, tiredness, loss of appetite and trouble sleeping. There is some strong scientific evidence that it is effective for mild to moderate depression.

Other uses include heart palpitations, moodiness and other symptoms of menopause, mental disorders that present physical symptoms, premenstrual syndrome (PMS), attention deficit-hyperactivity disorder (ADHD), obsessive-compulsive disorder (OCD), social phobia, and seasonal affective disorder (SAD).

St. John's wort has been tried to help quit smoking, for fibromyalgia, chronic fatigue syndrome (CFS), burning feelings in the mouth, migraine and other types of headaches, muscle pain, nerve pain and nerve damage throughout the body, pain that travels down the sciatic nerve in the leg, and irritable bowel syndrome. It is also used for cancer (including brain cancer), HIV/AIDS, hepatitis C, herpes simplex, to help with a procedure to unblock clogged arteries, weight loss, and to treat a disease that causes the skin to lose color.

An oil can be made from St. John's wort. Some people take this oil by mouth for indigestion. Some people apply this oil to their skin to treat bruises and scrapes, inflammation and muscle pain, scaly and itchy skin (psoriasis), first degree burns, wounds, tooth pulling, bug bites, hemorrhoids, nerve pain, and to treat a disease that causes the skin to lose color. But applying St. John's wort directly to the skin is risky. It can cause serious sensitivity to sunlight.

In manufacturing, St. John's wort extracts are also used in alcoholic beverages.

The active ingredients in St. John's wort can be deactivated by light. That's why you will find many products packaged in amber containers. The amber helps, but it doesn't offer total protection against the adverse effects of light.

Is St. John's Wort effective?

St. John's wort can help for treatment of mild to moderate depression. It's about as effective as some prescription drugs. However, it might not be as effective for severe depression.

There is also some scientific evidence that St. John's wort might be effective for treating anxiety.

Oily preparations of St. John's wort seem to help stomach upset when taken by mouth. When applied to the skin, these oily preparations seem to help first degree burns, cuts and bruises, and muscle pain.

There is also some evidence that St. John's wort is not effective for treating HIV infection. Don't use St. John's wort for this condition.

There isn't enough information to know if St. John's wort is effective for the other conditions people use it for, including: migraine headache, nerve pain, sciatica, excitability, muscle pain, cancer, obsessive compulsive behavior, premenstrual syndrome (PMS), and many others.

Likely Effective for...

  • Depression. Taking St. John's wort extracts improves mood and decreases anxiety and insomnia related to depression. It seems to be about as effective in treating depression as many prescription drugs. In fact, clinical guidelines from the American College of Physicians-American Society of Internal Medicine suggest that St. John's wort can be considered an option along with antidepressant medications for short-term treatment of mild depression. However, since St. John's wort does not appear to be more effective or significantly better tolerated than antidepressant medications, and since St. John's wort causes many drug interactions, the guidelines suggest it might not be an appropriate choice for many people, particularly those who take other medications. St. John's wort might not be as effective for more severe cases of depression.

Possibly Effective for...

  • Menopausal symptoms. Some evidence suggests that some specific combinations of St. John's wort plus black cohosh (Remifemin; Gynoplus, Jin-Yan Pharm) can help improve menopausal symptoms such as hot flashes. The effects of St. John's wort alone on menopausal symptoms are inconsistent. Some, but not all, research suggests that St. John's wort might reduce hot flashes. However, St. John's wort does not seem to improve sleep, quality of life, or other menopausal symptoms when used alone.
  • The conversion of mental experiences or states into bodily symptoms (somatization disorder). Treatment with a specific St. John's wort product (LI 160, Lichtwer Pharma) daily for 6 weeks seems to reduce symptoms of somatization disorder.
  • Wound healing. Applying an ointment containing St. John's wort three times daily for 16 days seems to improve wound healing and reduce scar formation after a Cesarean section (C-section).

Possibly Ineffective for...

  • Burning mouth syndrome. Taking St. John's wort three times daily for 12 weeks does not reduce pain from burning mouth syndrome.
  • Hepatitis C virus (HCV) infection. Taking St. John's wort by mouth does not seem to be effective for treating adults with hepatitis C virus infection.
  • HIV/AIDS. Taking St. John's work by mouth does not seem to be effective for treating HIV-infected adults.
  • Irritable bowel syndrome (IBS). Early research shows that taking a specific St. John's wort extract (St. John's Wort Extract Extra Strength, Enzymatic Therapy) twice daily is not effective for reducing symptoms of IBS.
  • Nerve damage outside the brain or spinal cord (polyneuropathy). Taking St. John's wort by mouth does not seem to relieve pain in diabetic or non-diabetic people with polyneuropathy.
  • Social phobia. Taking St. John's wort daily does not seem to improve social phobia or social anxiety.

Insufficient Evidence to Rate Effectiveness for...

  • A procedure to widen blocked arteries (angioplasty). Early research shows that taking St. John's wort three times daily for 2 weeks after a procedure to widen blocked arteries improves outcomes of the procedure in people who are also taking blood thinning medications. It is thought that St. John's wort might help the blood thinning medications work better in some people.
  • Anxiety. Some reports suggest that taking St. John's wort alone or together with valerian improves anxiety disorder. Also, taking one capsule of a specific product that contains St. John's wort and valerian root (Sedariston Concentrate, Aristo Pharma GmbH) daily for one week, followed by one or two capsules twice daily for another week, reduces anxiety more than the medication diazepam.
  • Attention deficit-hyperactivity disorder (ADHD). Some research suggests that taking St. John's wort daily for 4 weeks might improve attention and activity in adolescents with ADHD. But other research shows that taking a St. John's wort extract for 8 weeks does not improve ADHD symptoms in children ages 6-17 years.
  • Brain tumor (glioma). Early research shows that taking hypericin, a chemical in St. John's wort, by mouth for up to 3 months might reduce tumor size and improve the survival rate in people with brain tumors.
  • Herpes. Early research suggests that using a specific combination of St. John's wort and copper sulfate pentahydrate (Dynamiclear) might help reduce symptoms, including stinging, burning and pain, in people with cold sores or genital herpes.
  • Migraine headache. Early research suggests that taking a specific St. John's wort product (Perforan, Godaru, Iran) three times daily improves the severity of migraine pain but does not reduce how often migraines occur.
  • Obsessive-compulsive disorder (OCD). There is conflicting evidence about the effectiveness of St. John's wort for OCD. The reason for contradictory findings could be due to differences in study design, differences in the St. John's wort products used, or other factors.
  • Skin redness and irritation (plaque psoriasis). Early research suggests that applying St. John's wort liquid or ointment to the skin decreases the severity and the size of psoriasis patches.
  • Premenstrual syndrome (PMS). There is conflicting evidence about the use of St. John's wort for treating PMS. Some early research suggests that St. John's wort might help reduce PMS symptoms, including sleeping problems, coordination, confusion, crying, headache, fatigue, food cravings and swelling, by even as much as 50% in some women. However, other research shows that taking St. John's wort does not reduce anxiety or other PMS symptoms.
  • Seasonal affective disorder (SAD). Early studies suggest that St. John's wort might help SAD. It appears to improve symptoms of anxiety, decreased sex drive, and sleep disturbances associated with SAD. It is useful alone or in combination with light therapy.
  • Smoking cessation. Early research suggests that taking a specific St. John's wort extract (LI-160, Lichtwer Pharma US) once or twice daily starting one week before and continuing for 3 months after quitting smoking does not improve long-term quit rates.
  • Tooth pulling. Early research suggests that applying a homeopathic St. John's wort preparation does not improve dental pain after a tooth is pulled or after dental surgery.
  • Stomach upset.
  • Bruises.
  • Skin conditions.
  • Nerve pain.
  • Sciatica.
  • Excitability.
  • Fibromyalgia.
  • Chronic fatigue syndrome (CFS).
  • Muscle pain.
  • Cancer.
  • Weight loss.
  • Other conditions.
More evidence is needed to rate St. John's wort for these uses.

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).

Therapeutic Research Faculty copyright

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