Myrtaceae
Guava Leaf
Psidium guajava
✓ Generally Safe
Caution in Pregnancy
Native to: Central America, Caribbean (cultivated tropically)
Also known as: Common Guava Leaf, Tropical Guava, Apple Guava
Wikimedia Commons / CC BY-SA
Parts Used
LeafFruit
Therapeutic Uses
Acute diarrhea and gastroenteritis (WHO recommendation for developing countries — clinical trials), type 2 diabetes (leaf — reduces blood sugar), oral infections (antimicrobial gargle), wound healing.
Herbal Actions
Antidiarrheal, antimicrobial, antifungal, antidiabetic, antispasmodic, antioxidant
Active Constituents
Quercetin, isoflavonoids (farrerol, guaijaverin), tannins (guavin B — antidiarrheal), essential oil (caryophyllene, nerolidiol), vitamin C (fruit — 228mg/100g), lycopene (pink fruit)
Preparation Methods
☕ Herbal Tea💊 Capsule
Traditional Preparation Notes
| Herbal Tea | 3–5 dried leaves per 250ml, steep 15 min or simmer 10 min, 3x daily during diarrhea |
| Tincture | Standardized extract: 400mg 3x daily for blood sugar. Tea for diarrhea. |
| Notes | WHO lists guava leaf tea as effective for acute diarrhea in resource-limited settings. For blood sugar: 400mg extract before meals. Guavin B (tannin) directly inhibits intestinal secretion. Combine with oral rehydration salts for diarrhea. |
Safety Information
Safety Rating
✓ Generally Safe
Pregnancy
Caution in Pregnancy
Drug Interactions
Possible — consult doctor
Contraindications: Caution with antidiabetics (blood sugar lowering). May delay drug absorption (tannins). Caution in pregnancy at therapeutic doses.
Side Effects: Constipation with excessive use (astringent tannins). Rarely GI upset. Very well tolerated generally.