Yarrow may interact with the following medications:
Medications to reduce stomach acid -- Because yarrow may increase the production of stomach acid, it can interfere with both over-the-counter and prescription drugs including:
Medications for high blood pressure -- Yarrow may lower blood pressure slightly, and could make the effects of any prescription drugs you take to lower blood pressure stronger.
Drugs that cause sleepiness -- Because yarrow is a mild sedative, it can increase the effects of other drugs you take for anxiety or sleepiness. These include:
Achillea millefolium; Milfoil; Yarrow