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Eucalyptus


What is it?

Eucalyptus is a tree. The dried leaves and oil are used to make medicine. Though eucalyptus is used medicinally for many purposes, there isn’t enough scientific evidence so far to rate it as effective for any of them.

Eucalyptus leaf is used for infections, fever, upset stomach, and to help loosen coughs. The leaf is also used for treating respiratory tract infections, whooping cough, asthma, pulmonary tuberculosis, osteoarthritis, joint pain (rheumatism), acne, wounds, poorly healing ulcers, burns, bacterial dysentery, ringworms, liver and gallbladder problems, loss of appetite, and cancer.

Eucalyptus oil should not be taken by mouth or applied to the skin full-strength. It must be diluted for safety. The diluted oil is taken by mouth for pain and swelling (inflammation) of respiratory tract mucous membranes, coughs, bronchitis, sinus pain and inflammation, asthma, chronic obstructive pulmonary disease (COPD), and respiratory infections. It is also used as an expectorant to loosen coughs, antiseptic, fever reducer, and in vaporizer fluids. Other uses include treatment of wounds, burns, ulcers, and cancer.

Diluted eucalyptus oil is applied directly to the skin for pain and swelling of respiratory tract mucous membranes, joint pain, genital herpes, and nasal stuffiness. It is also used as an insect repellent.

In dentistry, eucalyptus oil is included in products used as sealers and solvents for root canal fillings.

In foods, dried eucalyptus leaf is used as a flavoring agent.

In manufacturing, eucalyptus oil is used as a fragrance in perfumes and cosmetics. It is also used as a mouthwash, antiseptic, liniment and ointment, and in toothpaste, cough drops, and lozenges.

How effective is it?

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, Ineffective, and Insufficient Evidence to Rate.

The effectiveness ratings for EUCALYPTUS are as follows:

Possibly effective for...

  • Bronchitis. Some research shows that taking a specific combination product containing eucalyptol, a chemical found in eucalyptus oil, and extracts of pine and lime by mouth for at least 2 weeks improves symptoms and reduces flare-ups in people with bronchitis.
  • Insect repellant. Some research shows that applying a specific spray containing a combination of eucalyptus and lemon extract to the skin lowers the number of tick bites by about 30% in people living in tick-infested areas.

Insufficient evidence to rate effectiveness for...

  • Arthritis. Early research suggests that aromatherapy with a combination of eucalyptus oil, lavender, marjoram, rosemary, and peppermint oils might reduce pain and depression in people with arthritis.
  • Asthma. Early research suggests that eucalyptol, a chemical found in eucalyptus oil, might be able to break up mucous in people with asthma. Some people with severe asthma have been able to lower their dosage of steroid medications if they take eucalyptol. But don’t try this without your healthcare provider’s advice and monitoring.
  • Dental plaque. Early research suggests that chewing gum containing 0.3% eucalyptus extract might reduce dental plaque in some people.
  • Headache. Early research suggests that applying a combination product containing eucalyptus oil, peppermint oil, and ethanol to the head does not reduce pain in people with headaches. However, the product might help people with headaches relax and think better.
  • Stuffy nose.
  • Wounds.
  • Burns.
  • Ulcers.
  • Acne.
  • Bleeding gums.
  • Bladder diseases.
  • Diabetes.
  • Fever.
  • Flu.
  • Liver and gallbladder problems.
  • Loss of appetite.
  • Other conditions.
More evidence is needed to rate the effectiveness of eucalyptus for these uses.

How does it work?

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Eucalyptus leaf contains chemicals that might help control blood sugar. It also contains chemicals that might have activity against bacteria and fungi. Eucalyptus oil contains chemicals that might help pain and inflammation. It might also block chemicals that cause asthma.

Are there safety concerns?

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Eucalyptus leaf isLIKELY SAFE when consumed in the small amounts found in foods. There isn't enough information to know if supplements that contain larger amounts of eucalyptus leaf are safe when taken by mouth.

Eucalyptol, a chemical that is removed from eucalyptus oil and used as medicine, is POSSIBLY SAFE when taken by mouth for up to 12 weeks.

Eucalyptus oil is POSSIBLY UNSAFE when applied directly to the skin without first being diluted. Eucalyptus oil is LIKELY UNSAFE when it is taken by mouth without first being diluted. Taking 3.5 mL of undiluted oil can be fatal. Signs of eucalyptus poisoning might include stomach pain and burning, dizziness, muscle weakness, small eye pupils, feelings of suffocation, and some others. Eucalyptus oil can also cause nausea, vomiting, and diarrhea.

Special precautions & warnings:

Pregnancy and breast-feeding: Eucalyptus is LIKELY SAFE for pregnant and breast-feeding women when consumed in food amounts. But don’t use eucalyptus oil. Not enough is known about safety during pregnancy or breast-feeding.

Children: Eucalyptus oil is LIKELY UNSAFE for children. It should not be taken by mouth or applied to the skin. Not much is known about the safety of using eucalyptus leaves in children. It’s best to avoid use in amounts larger than food amounts.

Diabetes: Early research suggests eucalyptus leaf might lower blood sugar. There is concern that using eucalyptus while taking medications for diabetes might lower blood sugar too much. Blood sugar levels should be monitored closely.

Surgery: Since eucalyptus might affect blood sugar levels, there is concern that it might make blood sugar control difficult during and after surgery. Stop using eucalyptus at least 2 weeks before a scheduled surgery.

Are there interactions with medications?

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Moderate

Be cautious with this combination.

Aminopyrine
Inhaling eucalyptol, a chemical found in eucalyptus oil, might reduce the level of aminopyrine in the blood. In theory, the effectiveness of aminopryine may be reduced in people who inhale eucalyptol.

Amphetamines
Inhaling eucalyptol, a chemical found in eucalyptus oil, might reduce the levels of amphetamines in the blood. In theory, the effectiveness of amphetamines may be reduced in people who inhale eucalyptol.

Medications changed by the liver (Cytochrome P450 1A2 (CYP1A2) substrates)
Some medications are changed and broken down by the liver. Eucalyptus oil might decrease how quickly the liver breaks down some medications. Taking eucalyptus oil along with some medications that are broken down by the liver can increase the effects and side effects of some medications. Before taking eucalyptus oil, talk to your healthcare provider if you take any medications that are changed by the liver.

Some medications that are changed by the liver include amitriptyline (Elavil), haloperidol (Haldol), ondansetron (Zofran), propranolol (Inderal), theophylline (Theo-Dur, others), verapamil (Calan, Isoptin, others), and others.

Medications changed by the liver (Cytochrome P450 2C19 (CYP2C19) substrates)
Some medications are changed and broken down by the liver. Eucalyptus oil might decrease how quickly the liver breaks down some medications. Taking eucalyptus oil along with some medications that are broken down by the liver can increase the effects and side effects of some medications. Before taking eucalyptus oil, talk to your healthcare provider if you take any medications that are changed by the liver.

Some medications that are changed by the liver include omeprazole (Prilosec), lansoprazole (Prevacid), and pantoprazole (Protonix); diazepam (Valium); carisoprodol (Soma); nelfinavir (Viracept); and others.

Medications changed by the liver (Cytochrome P450 2C9 (CYP2C9) substrates)
Some medications are changed and broken down by the liver. Eucalyptus oil might decrease how quickly the liver breaks down some medications. Taking eucalyptus oil along with some medications that are broken down by the liver can increase the effects and side effects of some medications. Before taking eucalyptus oil, talk to your healthcare provider if you take any medications that are changed by the liver.

Some medications that are changed by the liver include diclofenac (Cataflam, Voltaren), ibuprofen (Motrin), meloxicam (Mobic), and piroxicam (Feldene); celecoxib (Celebrex); amitriptyline (Elavil); warfarin (Coumadin); glipizide (Glucotrol); losartan (Cozaar); and others.

Medications changed by the liver (Cytochrome P450 3A4 (CYP3A4) substrates)
Some medications are changed and broken down by the liver. Eucalyptus oil might decrease how quickly the liver breaks down some medications. Taking eucalyptus oil along with some medications that are broken down by the liver can increase the effects and side effects of some medications. Before taking eucalyptus oil, talk to your healthcare provider if you are taking any medications that are changed by the liver.

Some medications changed by the liver include lovastatin (Mevacor), ketoconazole (Nizoral), itraconazole (Sporanox), fexofenadine (Allegra), triazolam (Halcion), and many others.

Medications for diabetes (Antidiabetes drugs)
Eucalyptus leaf extract might decrease blood sugar. Diabetes medications are also used to lower blood sugar. Taking eucalyptus leaf extract along with diabetes medications might cause your blood sugar to go too low. Monitor your blood sugar closely. The dose of your diabetes medication might need to be changed.

Some medications used for diabetes include glimepiride (Amaryl), glyburide (DiaBeta, Glynase PresTab, Micronase), insulin, pioglitazone (Actos), rosiglitazone (Avandia), chlorpropamide (Diabinese), glipizide (Glucotrol), tolbutamide (Orinase), and others.

Pentobarbital (Nembutal)
Inhaling eucalyptol, a chemical found in eucalyptus oil, might reduce the amount of pentobarbital that reaches the brain. In theory, the effectiveness of pentobarbital may be reduced in people who inhale eucalyptol.

Are there interactions with herbs and supplements?

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Herbs and supplements that might lower blood sugar
Eucalyptus leaf might lower blood sugar. Using it with other herbs and supplements that have this same effect might increase the risk of low blood sugar in some people. Some of these products include alpha-lipoic acid, bitter melon, carqueja, chromium, devil's claw, fenugreek, garlic, guar gum, horse chestnut, jambolan, Panax ginseng, prickly pear cactus, psyllium, Siberian ginseng, and others.

Herbs that contain hepatotoxic pyrrolizidine alkaloids (PAs)
Eucalyptus can increase the toxicity of herbs that contain hepatotoxic pyrrolizidine alkaloids (PAs). PAs can damage the liver. Herbs containing hepatotoxic PAs include alkanna, boneset, borage, butterbur, coltsfoot, comfrey, forget-me-not, gravel root, hemp agrimony, and hound's tongue; and the Senecio species plants dusty miller, groundsel, golden ragwort, and tansy ragwort.

Are there interactions with foods?

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There are no known interactions with foods.

What dose is used?

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The appropriate dose of eucalyptus depends on several factors such as the user's age, health, and several other conditions. At this time there is not enough scientific information to determine an appropriate range of doses for eucalyptus. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult your pharmacist or physician or other healthcare professional before using.

Other names

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Blue Gum, Blue Mallee, Blue Mallee Oil, Eucalipto, Eucalypti Folium, Eucalyptol, Eucalyptol Oil, Eucalyptus blatter, Eucalyptus bicostata, Eucalyptus Essential Oil, Eucalyptus Oil, Eucalyptus fructicetorum, Eucalyptus globulus, Eucalyptus Leaf, Eucalyptus odorata, Eucalyptus Oil, Eucalyptus polybractea, Eucalyptus smithii, Fever Tree, Fieberbaumblatter, Gully Gum, Gully Gum Oil, Gum Tree, Huile Essentielle d’Eucalyptus, Huile d’Eucalyptol, Huile d’Eucalyptus, Red Gum, Stringy Bark Tree, Sugandhapatra, Tailapatra, Tasmanian Blue Gum.

Methodology

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To learn more about how this article was written, please see the Natural Medicines Comprehensive Database methodology.methodology (http://www.nlm.nih.gov/medlineplus/druginfo/natural/methodology.html).

References

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To see all references for the Eucalyptus page, please go to http://www.nlm.nih.gov/medlineplus/druginfo/natural/700.html.

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  2. Day, L. M., Ozanne-Smith, J., Parsons, B. J., Dobbin, M., and Tibballs, J. Eucalyptus oil poisoning among young children: mechanisms of access and the potential for prevention. Aust N.Z.J Public Health 1997;21:297-302. View abstract.
  3. Jori, A., Bianchetti, A., Prestini, P. E., and Gerattini, S. Effect of eucalyptol (1,8-cineole) on the metabolism of other drugs in rats and in man. Eur.J Pharmacol 1970;9:362-366. View abstract.
  4. Kim, M. J., Nam, E. S., and Paik, S. I. [The effects of aromatherapy on pain, depression, and life satisfaction of arthritis patients]. Taehan Kanho.Hakhoe.Chi 2005;35:186-194. View abstract.
  5. Matthys, H., de Mey, C., Carls, C., Rys, A., Geib, A., and Wittig, T. Efficacy and tolerability of myrtol standardized in acute bronchitis. A multi-centre, randomised, double-blind, placebo-controlled parallel group clinical trial vs. cefuroxime and ambroxol. Arzneimittelforschung. 2000;50:700-711. View abstract.
  6. Meister, R., Wittig, T., Beuscher, N., and de Mey, C. Efficacy and tolerability of myrtol standardized in long-term treatment of chronic bronchitis. A double-blind, placebo-controlled study. Study Group Investigators. Arzneimittelforschung. 1999;49:351-358. View abstract.
  7. Swanston-Flatt SK, Day C, Bailey CJ, Flatt PR. Traditional plant treatments for diabetes. Studies in normal and streptozotocin diabetic mice. Diabetologia 1990;33:462-4. View abstract.
  8. Vigo E, Cepeda A, Gualillo O, Perez-Fernandez R. In-vitro anti-inflammatory effect of Eucalyptus globulus and Thymus vulgaris: nitric oxide inhibition in J774A.1 murine macrophages. J Pharm Pharmacol 2004;56:257-63. View abstract.
  9. Whitman BW, Ghazizadeh H. Eucalyptus oil: therapeutic and toxic aspects of pharmacology in humans and animals. J Paediatr Child Health 1994;30:190-1. View abstract.
  10. Juergens UR, Dethlefsen U, Steinkamp G, et al. Anti-inflammatory activity of 1.8-cineol (eucalyptol) in bronchial asthma: a double-blind placebo-controlled trial. Respir Med 2003;97:250-6. View abstract.
  1. Gardulf A, Wohlfart I, Gustafson R. A prospective cross-over field trial shows protection of lemon eucalyptus extract against tick bites. J Med Entomol 2004;41:1064-7. View abstract.
  2. Gray AM, Flatt PR. Antihyperglycemic actions of Eucalyptus globulus (Eucalyptus) are associated with pancreatic and extra-pancreatic effects in mice. J Nutr 1998;128:2319-23. View abstract.
  3. Takahashi T, Kokubo R, Sakaino M. Antimicrobial activities of eucalyptus leaf extracts and flavonoids from Eucalyptus maculata. Lett Appl Microbiol 2004;39:60-4. View abstract.
  4. Darben T, Cominos B, Lee CT. Topical eucalyptus oil poisoning. Australas J Dermatol 1998;39:265-7. View abstract.
  5. Burkhard PR, Burkhardt K, Haenggeli CA, Landis T. Plant-induced seizures: reappearance of an old problem. J Neurol 1999;246:667-70. View abstract.
  6. De Vincenzi M, Silano M, De Vincenzi A, et al. Constituents of aromatic plants: eucalyptol. Fitoterapia 2002;73:269-75. View abstract.
  7. Silva J, Abebe W, Sousa SM, et al. Analgesic and anti-inflammatory effects of essential oils of Eucalyptus. J Ethnopharmacol 2003;89:277-83. View abstract.
  8. White RD, Swick RA, Cheeke PR. Effects of microsomal enzyme induction on the toxicity of pyrrolizidine (Senecio) alkaloids. J Toxicol Environ Health 1983;12:633-40. View abstract.
  9. Unger M, Frank A. Simultaneous determination of the inhibitory potency of herbal extracts on the activity of six major cytochrome P450 enzymes using liquid chromatography/mass spectrometry and automated online extraction. Rapid Commun Mass Spectrom 2004;18:2273-81. View abstract.
  10. Electronic Code of Federal Regulations. Title 21. Part 182 -- Substances Generally Recognized As Safe. Available at: http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid= 786bafc6f6343634fbf79fcdca7061e1&rgn=div5&view= text&node=21:3.0.1.1.13&idno=21
  11. Gobel H, Schmidt G, Soyka D. Effect of peppermint and eucalyptus oil preparations on neurophysiological and experimental algesimetric headache parameters. Cephalalgia 1994;14:228-34;discussion 182. View abstract.
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Last reviewed - 11/13/2014




Page last updated: 10 December 2014