Table 3 Mechanism of herb-drug interactions

Aesculus

hippocastanum/horse chestnut

Venous insufficiency

SM aesculin a hydroxycoumarin; ↑ anticoagulants.

A, I

[2]

Aloe barbadensis/aloe vera

Laxative, hypercholesterolemia

Laxative; causes hypokalemia: ↑ cardiac glycosides and antiarrhythmic drugs.

I

[82]

Ammi visnaga/khella

Muscle spasms

SM khellin; inhibits cytochrome P 450 enzymes: anticoagulants ↑, calcium channel blockers.

Not known

[85]

Angelica sinensis/angelica

Antitumour, antiinflammatory, analgesic, antispasmodic, dyspepsia, infection

Decreases prothrombin time ↑; anticoagulants, calcium channel blockers.

A

[88]

Cassia senna/senna

Laxative

Causes hypokalemia; ↑ cardiac glycosides + antiarrhythmic drugs and calcium channel blockers.

I

[84]

Chondrus crispus/irish moss

Ulcers, gastritis

Exerts anti-thrombin activity similar to heparin; ↑ anticoagulants and antihypertensives.

Not known

[58]

Cimifuga racemosa/black cohosh

Gynaecological ailments and premenstrual tension

Inhibits CYP3A4

Not known

[42, 76]

Glycyrrhiza glabra/licorice

Gastric ulcers

Causes hypokalemia reduces water and sodium excretion ↑; cardiac glycosides, ↓ thiazide and loop diuretics.

A, I

[86]

Hapagophytum Procumbens/devil’s claw

Anti-inflammatory

Inhibits cytochrome P 450 enzymes mainly CYP1A2 and CYP2D6; ↑ anticoagulants, statins and antihypertensives.

A

[55]

Hydrastis Canadensis/golden seal

Antiinflammatory, antimicrobial

Inhibits cytochrome P 450 enzymes mostly CYP3A4 and CYP2D6; ↑ antihypertensives, calcium channel blockers and digoxin

Anta, A

[56]

Oleum Oenotherae Biennis/evening primrose oil

Menopausal symptoms

Inhibits platelet activating factor; anticoagulants

Unknown

[87]

Zingiber officinalis/ginger

Antiemetic

Inhibits thromboxane synthase, acts as a prostacyclin agonist and large doses enhance hypothrombinaemia ↑; platelet inhibitors, anticoagulants and antihypertensives.

A

[89]