What side effects should I expect?

One of the most important side effects is the increased sensitivity to sunlight. This especially affects fair-skinned persons. Redness and even burns on the skin may occur.

With people who speak of a light allergy, it should be inquired whether they use St. John’s wort oil preparations. Many are not aware of this side effect. Sensitivity to light and thus avoidance of light can have strong effects on everyday life, well-being and mood.

This side effect can lead to severe depression. In addition, gastrointestinal complaints such as a feeling of fullness or constipation can occur. Less frequently, allergic reactions occur due to phospholipids from soybeans.

The so-called “Ponceau 4R” can cause hypersensitivity. Tiredness or inner restlessness can also occur. In aromatherapy, St. John’s wort oil can cause headaches in some people.

Other side effects may occur, which may be triggered by other ingredients in the preparations. In addition, some side effects may be unknown, as they are not associated with St. John’s wort oil. The active ingredient hypericin is known to cause sensitivity to sunlight.

This can lead to slight redness up to severe burns and is one of the most important side effects. Some preparations do not contain hypericin. This makes them more tolerable to the sun.

There are no known general interactions with alcohol. There are authors who have reported a positive effect of St. John’s wort oil in addiction problems with alcohol in rats and in humans. This is controversially discussed.

With which drugs can interactions occur?

St. John’s wort oil reduces the effect of various medicines. In particular, the active ingredient hypericin ensures a so-called enzyme induction of cytochrome P450-3A4. This means that it lowers the plasma level of substances and drugs that are also metabolized by the enzyme mentioned.

This reduces the effect of the other drugs. This can have fatal consequences. It affects drugs such as midazolam (a benzodiazepine), the contraceptive pill or cyclosporine A (an immunosuppressive drug).

Cyclosporine A plays an important role in organ transplants. It is used to prevent rejection of the transplants that are foreign to the body.The active ingredients of St. John’s wort oil could accelerate the breakdown of cyclosporin A. As a result, the drug may not be able to fulfill its function.

In this case, there would be a risk of transplant rejection due to the St. John’s wort oil. St. John’s wort oil can also interact with anticoagulants. This concerns the active ingredients phenprocoumon, warfarin and ticlopidine.

Furthermore, a combined treatment with St. John’s wort oil can reduce the effect of the active ingredient theophylline in certain asthma preparations. St. John’s wort oil should also be avoided when taking certain heart medication, so-called glycosides. In addition, studies have shown that cancer and AIDS medications lose almost 60% of their effect when St. John’s wort oil preparations are taken at the same time.

This affected drugs such as indinavir, imatinib, irinotecan and nebirapine. Caution is also required when taking other antidepressants at the same time. Here there is a risk of developing a so-called “serotonin syndrome”.

This can be accompanied by In some cases the serotonin syndrome can be fatal. Also, certain medications such as insulin and gliclazides, which are taken in the context of diabetes mellitus, can interact with St. John’s wort oil. It also has an effect on so-called blood lipid reducers.

It could also be that the oil makes the occasional intake of aspirin for headaches or a stomach-protecting drug like omeprazole ineffective. For these reasons it is very important to inform the doctor when St. John’s wort oil and other medications are taken.

Drop in blood pressure,
Sweating,
Restlessness,
Tremble
Up to and including coma.