Which herb is contraindicated in pregnancy, breastfeeding, glaucoma, tachycardia, and urinary retention?

• A. Avena sativa
• B. Boswellia serrata
• C. Calendula officinalis
• D. Atropa belladonna

Answer: (D)

The key idea is that this herb contains potent antimuscarinic (anticholinergic) alkaloids, which disrupt multiple body systems by blocking muscarinic receptors. Those effects dry secretions, relax smooth muscles, and slow or alter autonomic signaling. In the eye, anticholinergics dilate the pupil and can raise intraocular pressure, making glaucoma a clear contraindication. In the heart, they raise heart rate, which is problematic for tachycardia. In the bladder, they reduce detrusor muscle activity, leading to urinary retention. They can also cross the placenta and appear in breast milk, posing risks to pregnancy and nursing infants. Because of these broad, potentially serious effects, this herb is contraindicated in pregnancy, breastfeeding, glaucoma, tachycardia, and urinary retention.

The other herbs listed do not carry this same potent anticholinergic risk profile and are not described as contraindicated in all of those conditions.