Yarrow (Achillea millefolium): traditional uses, preparation methods, studied properties, and contraindications of this European plant.

Guava (Psidium guajava): traditional uses, leaf tea preparation, studied properties, and contraindications for diarrhea and diabetes.

Comfrey (Symphytum officinale): traditional topical uses in poultices and ointments, plus the essential contraindications for internal consumption.

White willow (Salix alba): traditional uses, bark decoction preparation, and contraindications for Reye's syndrome, salicylate allergy, and anticoagulants.

Borage (Borago officinalis): traditional uses, seed oil and infusion preparation, properties, and contraindications in pregnancy and breastfeeding.