Drug Interactions

Herb–Drug Interaction

TRBitki–İlaç Etkileşimi
Also known as:Herbal–drug interaction · Botanical–drug interaction

An interaction between a herbal medicine or botanical supplement and a conventional drug that alters the drug's pharmacokinetics or pharmacodynamics.

In depth

The best-documented example is St. John's wort (Hypericum perforatum), whose constituent hyperforin activates PXR and induces CYP3A4, other CYPs and P-glycoprotein, lowering concentrations of ciclosporin, tacrolimus, hormonal contraceptives, several antiretrovirals, digoxin and warfarin; it also adds serotonergic effects to antidepressants. Other herbs raise concern mainly through pharmacodynamic effects, such as a possible additive bleeding risk with ginkgo and anticoagulants.

Assessment is difficult because product composition varies between batches and manufacturers, active constituents are often poorly characterized, and patients frequently do not report herbal use.

Clinical pearl

Herbal products, teas and supplements should be asked about specifically, as patients rarely volunteer them; St. John's wort can precipitate transplant rejection or contraceptive failure.

Example drugs

ciclosporin Tacrolimus Warfarin Digoxin
TRIn Turkish

Bitki–İlaç Etkileşimi

Bitkisel bir ilaç veya bitkisel takviye ile konvansiyonel bir ilaç arasında, ilacın farmakokinetiğini veya farmakodinamiğini değiştiren etkileşimdir.

En iyi belgelenmiş örnek sarı kantarondur (Hypericum perforatum); içerdiği hiperforin PXR'yi aktive ederek CYP3A4'ü, diğer CYP'leri ve P-glikoproteini indükler ve siklosporin, takrolimus, hormonal kontraseptifler, bazı antiretroviral ilaçlar, digoksin ve varfarin konsantrasyonlarını düşürür; ayrıca antidepresanlara serotonerjik etki ekler. Diğer bitkilerde endişe daha çok farmakodinamiktir; ginkgonun antikoagülanlarla olası aditif kanama riski buna örnektir.

Ürün bileşimi seriler ve üreticiler arasında değiştiğinden, etkin bileşenler çoğu zaman yeterince tanımlanmadığından ve hastalar bitkisel ürün kullanımını sıklıkla bildirmediğinden değerlendirme güçtür.

Hastalar bitkisel ürünleri, çayları ve takviyeleri kendiliğinden nadiren belirttiği için bunlar özellikle sorgulanmalıdır; sarı kantaron transplant reddine veya kontrasepsiyon başarısızlığına yol açabilir.

Diğer adları:Bitkisel ürün–ilaç etkileşimi · Bitkisel ilaç etkileşimi
Updated 24.09.2026 0 views Educational reference — verify against current sources before clinical use.

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