Cinnamon - Drug Interactions, Side Effects and Precautions of Use
Common Trade Names
None known. Various manufacturers produce cinnamon for use as a spice for foods.
Available as cinnamon oil, dried bark and leaves, and powder.
Active components are derived from the dried bark, leaves, and twigs of various species of Cinnamomum: Ceylon cinnamon (C. zeylanicum), Saigon cinnamon (C. loureirii), and others. C. zeylanicum grows in Sri Lanka, southeastern India, Indonesia, South America, and the West Indies. Essential oils are removed by steam distillation of the dried bark and leaves.
The main element in the essential oil is cinnamaldehyde. Other components found in smaller amounts include phenols and terpenes (such as eugenol, trans-cinnamic acid, hydroxycinamaldehyde, O-methoxycinnamaldehyde, a-glucoside, and 3-(2-hydroxyphenol)-propanoic acid), cinnamyl alcohol, tannins, mucilage, procyanidins, and coumarins.
Eugenol has antiseptic and anesthetic properties. Cinnamic aldehyde has shown fungicidal activity in vitro against such respiratory tract mycoses as Aspergillus flavus, A. fuigatis, A. midulans, A. niger, Candida albicans, Candida tropicalis, Cryptococcus neoformans, and Histoplasma . O-glucoside and 3-(2-hydroxyphenol)propanoic acid have reportedly demonstrated gastroprotective activity in rats similar to that of cimetidine. Cinnamon extracts have also demonstrated analgesic and antioxidant properties in rodent studies.
Cinnamon oil is widely used in small amounts in detergents, gargles, liniments, lotions, mouthwashes, soaps, toothpaste, and other pharmaceutical products and cosmetics. Claims have been made for cinnamon products as an analgesic, an antidiarrheal, and an antifungal. In Eastern and Western folk medicine, uses for cinnamon include treating abdominal pain, chest pain, chronic diarrhea, colds, female reproductive disorders, hypertension, kidney disorders, and rheumatism.
Cinnamon extracts have demonstrated significant inhibitory effects on strains of Helicobacter pylori and its urease, but a pilot study of an alcoholic cinnamon extract was ineffective in eradicating H. pylori in 15 subjects after twice-a-day dosing for 4 weeks .
No consensus exists. Most sources cite cinnamon's use as a spice in small quantities only.
CV: increased heart rate.
EENT: cheilitis, gingivitis, glossitis, perioral dermatitis, stomatitis.
GI: increased GI motility.
Skin: facial flushing.
Other: hypersensitivity reactions (including contact dermatitis, hand perspiration, post -excitatory state followed by a period of centralized sedation [drowsiness], second-degree burns), squamous cell carcinoma .
Contraindications And Precautions
Avoid using cinnamon in excess of amounts normally found in foods in pregnant or breast-feeding women.
Inform the patient that cinnamon should be used only as a spice. Other uses cannot be recommended because adequate data are lacking.
Advise the patient that cinnamon or its components can cause allergic reactions, such as skin irritation (including second-degree burns) and stomatitis.
Toxicity studies in rats suggest that chronic C. zeylanicum ingestion (90 days) may cause hepatic damage (reduction in liver weight) and a significant decrease in hemoglobin levels .
Urge the patient to report unusual signs or symptoms. Cinnamon toxicity involves the GI tract, CNS, and CV system.
Inform the patient that squamous cell carcinoma of the tongue has been linked to prolonged and heavy gum chewing (five packs/day) of cinnamon-flavored gum in one case report .
Alert Caution parents that children may use cinnamon products as a recreational drug.
Points of Interest
Cinnamon extracts inhibit the oxidation of various foodstuffs, suggesting a possible role as a food preservative.
Human trials evaluating the efficacy of cinnamon for its proposed uses are lacking. Further studies in animals and humans are needed to determine its safety and efficacy. Ingestion in quantities greater than that for use as a spice cannot be recommended.