St John's Wort

Hypericum perforatum

Daisy family (Asteraceae)

Energetics: warming, drying (De la Foret, n.d., Pivarnik, 2019)
Taste: bitter, pungent, sweet (De la Foret, n.d.)
When to harvest: Harvest flowers when it blooms around summer solstice; depending on the climate, it may bloom a bit earlier or later.
Identification: St John’s Wort is a perennial plant that prefers dry, sunny areas. The leaves have tiny holes that can be seen when held up to the light. The small 1cm flowers, when rubbed, will stain skin reddish-purple. It can grow up to 120cm tall.

Please note that this information is largely based on De la Foret (n.d.) except where noted. See Reference section for all reference details.

St John’s Wort is named for the Christian martyr, St John, because of the pigment released when the flower is rubbed, and perforatum in its Latin name refers to the tiny pinprick sized holes in the leaf. St John's Wort herb has come to be associated with depression treatment, but many herbalists consider it a minor herb for depression. It is more widely used by herbalists for nerve pain, wound healing, and liver support.

Nervous system

Restorative: St John’s Wort helps to restore the health of the nervous system if it has been depleted or weakened

Nerve pain: It alleviates nerve pain, such as from spinal injury, sciatica, or shingles

Herpes, cold sores, shingles: Herpes virus lives in nerve cells, and St John’s Wort can help prevent outbreaks and reduce severity or duration of outbreaks. Shingles, caused by a type of herpes virus called zoster virus, also results in nerve pain and painful rashes, which St John's Wort can help alleviate.

Liver support

If the liver is sluggish, it might be impeded from processing normal wastes and hormones well, which can result in hormonal or other imbalances. St John’s Wort improves particular metabolism pathways in the liver, helping to process and clear out things that need to be cleared out, and improve hormonal balance. This can help with premenstrual syndrome and other conditions of hormonal imbalance. However, because it impacts metabolism pathways, it can also clear out pharmaceuticals before they’ve had a chance to do their work.

Urinary system

St John’s Wort is a diuretic, promoting urination and excretion of fluid.

Wound healing, bruises, sprains

St John’s Wort can be used similarly to arnica to soothe bruises, wounds, sprains, or swellings, as it helps to modulate inflammation. It also helps with scar healing.

Sun protection

St John’s Wort applied topically can offer mild protection from sun damage. For some people, it may increase photosensitivity and cause sun damage, so it’s best to test out.

Plant Preparations


  • Infusion
  • Tincture


  • Oil of fresh flowers
  • Balm
  • Liniment


St John’s Wort can interfere with many pharmaceuticals, such as those listed below. For this reason, it’s best to avoid taking internally if one is taking any medication, unless consulting with a medical professional.

  • Immunosuppressants
  • Anticoagulants
  • Antiarrhythmics
  • Calcium channel blockers
  • Anti-anginals
  • Hormonal Contraceptives (unlikely interaction, according to more recent studies)
  • Anxiolytics
  • Antidepressants
  • Antivirals
  • Statins
  • Anticancer drugs, such as chemotherapies
  • Beta-adrenergic blockers
  • Hypoglycemics
  • Antiulcer agents
  • Antifungals
  • Anticonvulsants
  • Skeletal muscle relaxants
  • Antihistamines

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