Products
St. John’s wort and corresponding preparations are commercially available in the form of teas, film-coated tablets, dragées, capsules, and tinctures, among others (e.g., Jarsin, Rebalance, Remotiv, Ceres, Hyperiforce, Hyperiplant, Offenware).
Stem plant
Common St. John’s wort L. is a perennial plant of the St. John’s wort family, native to Europe and also common in many countries. If you hold the leaves up to the light, you will discover small translucent excretory receptacles that look like holes (hence ). The dark spots on the flowers contain the pigment hypericin.
Medicinal drug
St. John’s wort (Hyperici herba) consists of the dried, whole or cut shoot tips of L. harvested during flowering. Fresh St. John’s wort shoot tips (Hyperici summitates cum floribus recentes) consist of the whole shoot tips of L. harvested during flowering and not more than 15 cm long.
Preparations
Liquid or dry extracts are obtained from fresh or dried St. John’s wort using ethanol or methanol. Another product is St. John’s oil (Hyperici oleum), which is mainly used externally in folk medicine, e.g., for scars, minor burns, and wounds. It is usually made with sunflower oil, sometimes with olive oil.
Ingredients
The ingredients of the herb include:
- Anthranoids: naphthodianthrones: hypericin, pseudohypericin.
- Phloroglucin derivatives: hyperforin, adhyperforin.
- Flavonoids: hyperoside, rutoside, quercitrin, isoquercitrin, biflavone.
- Oligomeric procyanidins
- Xanthones
- Essential oil
Effects
St. John’s wort (ATC N06AX25) and its preparations have antidepressant and sedative properties. The preparations should be taken daily and the effects are delayed within two to four weeks. A treatment duration of at least four to six weeks is recommended. Various hypotheses exist regarding the mechanism of action. The effects are attributed to, among other things, inhibition of the reuptake of norepinephrine and serotonin into the presynaptic neuron.
Indications for use
For depressed mood, mood instability, inner restlessness, anxiety, states of tension, and associated disorders of falling asleep and staying asleep. For the treatment of mild and moderate depressive episodes.
Dosage
According to package insert. Finished medicines are taken one to three times daily with or after meals, depending on the extract and dose. The tea is drunk two to three times daily after meals.
Contraindications
- Hypersensitivity
- Light hypersensitivity
- Combination with some CYP substrates (applies to hyperforin-rich extracts).
- Antidepressants and other serotoninergic substances.
For complete precautions, see the drug label.
Interactions
Hyperforin-rich St. John’s wort extract is an inducer of CYP450 (including CYP3A4) and P-glycoprotein. This may result in a reduction in the plasma concentration of a CYP or P-gp substrate, thereby reversing the effects. Interactions are possible with, for example, immunosuppressants, HIV drugs, some cytostatics and vitamin K antagonists, digoxin, methadone, and hormonal contraceptives. Studies have shown that no interactions via CYP450 and P-glycoprotein are expected with extracts low in hyperforin such as Ze 117 from Zeller (see literature, SmPC). Distinguished:
- Low hyperforin extracts up to max. 1 mg hyperforin per daily dose.
- Hyperforin-rich extracts > 1 mg hyperforin per daily dose.
St. John’s wort should only be combined with caution with serotonergic agents, such as SSRIs or SSNRIs, because serotonin syndrome may occur.
Adverse effects
The most common possible adverse effects include headache, sweating, weakness, dizziness, and indigestion. Photosensitization may occur but is considered rare.
