Hysan Lavender Relaxing Oil by Hysan Pharmaceutical Co Ltd

LIKELY EFFECTIVE

• Cough. Topical camphor formulations seem to reduce acute cough. Details: Camphor is approved by the U.S. Food and Drug Administration as a topical antitussive (chest rub) in concentrations of less than 11% (4814).
• Pain (acute). Topical camphor formulations seem to reduce acute pain. Details: Camphor is approved by the U.S. Food and Drug Administration for topical use as an analgesic and anesthetic in concentrations of 3% to 11% (272,4814). It is used in many topical products to treat pain related to cold sores, insect stings and bites, minor burns, and hemorrhoids (272).
• Pruritus. Topical camphor formulations seem to reduce pruritus. Details: Camphor is approved by the U.S. Food and Drug Administration for topical use as an antipruritic agent in concentrations of 3% to 11% (272,4814).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Acne. Although there is interest in using topical camphor for acne, there is insufficient reliable information about the clinical effects of camphor for this condition.
• Insect bite. Topical camphor has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that applying a combination of camphor 2%, menthol 2%, and eucalyptus oil 4%, with or without an Indian herb mixture called Trikatu, reduces the papule size of mosquito bites after 1-3 hours (89893). However, it is unclear if the decrease in papule size is related to natural change or the treatment. Also, the effect of camphor alone is not clear.
• Onychomycosis. Although there is interest in using topical camphor for onychomycosis, there is insufficient reliable information about the clinical effects of camphor for this condition.
• Orthostatic hypotension. Oral camphor has only been evaluated in combination with hawthorn; its effect when used alone is unclear. Details: A meta-analysis of 4 small clinical studies in patients with orthostatic hypotension shows that giving single doses of 20-25 drops of a specific combination product (Korodin Herz-Kreislauf-Tropfen) containing camphor and hawthorn modestly increases systolic and diastolic blood pressure when compared with placebo (103620). However, the studies have methodologic problems and, while 2 were conducted in patients with orthostatic hypotension, the others involved healthy young adults or normotensive elderly subjects. The effect of camphor alone for treatment of orthostatic hypotension has not been determined. The combination product used in these studies is not available in the US.
• Osteoarthritis. Although topical camphor is approved for use in the management of acute pain due to its counterirritant effects, it is unclear if it is beneficial for knee osteoarthritis. Details: A small study in patients with knee osteoarthritis shows that applying a topical cream containing camphor 32 mg/gram, glucosamine sulfate30 mg/gram, chondroitin sulfate 50 mg/gram, shark cartilage 140 mg/gram, and peppermint oil 9 mg/gram as needed for 8 weeks seems to moderately reduce pain when compared with placebo (10327). More evidence is needed to rate camphor for these uses.

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INSUFFICIENT RELIABLE EVIDENCE to RATE

• Acne. Although there is interest in using topical eucalyptus for acne, there is insufficient reliable information about the clinical effects of eucalyptus for this condition.
• Asthma. A small clinical study suggests that taking the eucalyptol constituent of eucalyptus orally might have a steroid-sparing effect in some patients with asthma. Details: Preliminary clinical research in patients with steroid-dependent asthma shows that taking eucalyptol, a constituent of eucalyptus oil, 200 mg three times daily orally for 12 weeks, allows for an average reduction in prednisolone doses of 36%, compared with a 7% reduction in those taking placebo (13302).
• Bronchitis. Oral eucalyptol has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Some clinical research in patients with chronic bronchitis shows that taking a specific combination product containing eucalyptol and extracts of pine and lime (Myrtol standardized, MYS, Gelomyrtol forte) 900 mg daily orally for at least 1 month decreases the proportion of patients with acute exacerbations by 72%, compared with 53% for those taking placebo (48925). In patients with acute bronchitis, receiving the same product in a dose of 1200 mg daily for 14 days is associated with a reduction in symptoms in all but 1% of patients, compared with 32% of patients receiving placebo (48932).
• Burns. Although there is interest in using topical eucalyptus for burns, there is insufficient reliable information about the clinical effects of eucalyptus for this condition.
• Cancer. Although there is interest in using oral eucalyptus for cancer, there is insufficient reliable information about the clinical effects of eucalyptus for this condition.
• Chronic obstructive pulmonary disease (COPD). A small clinical study suggests that the eucalyptol constituent of eucalyptus might reduce acute exacerbations in patients with stable COPD. Details: Clinical research in adults with stable, moderate to severe COPD shows that adding eucalyptol, 200 mg three times daily, to conventional therapy for 6 months, including the winter season, reduces the proportion of patients experiencing acute exacerbations from 46% to 28% when compared with placebo (104960).
• Cough. Oral eucalyptus oil has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A meta-analysis of four clinical studies in patients with cough associated with bronchitis or upper respiratory tract infection shows that taking eucalyptus oil, either in combination with pine and lime essential oils (Myrtol or Gelomyrtol) or with Origanum syriacum, peppermint, and rosemary essential oils, daily for up to 6 months increases the likelihood of improvement or resolution of cough symptoms by 45% when compared with placebo (110095).
• Dental plaque. Using chewing gum containing eucalyptus extract might reduce dental plaque. Details: Preliminary clinical research shows that chewing gum containing 0.3% to 0.6% eucalyptus extract 3-5 times daily for 4 days to 12 weeks reduces dental plaque when compared with placebo (49010,92863).
• Diabetes. Although there is interest in using oral eucalyptus for diabetes, there is insufficient reliable information about the clinical effects of eucalyptus for this condition.
• Endotracheal intubation-associated adverse effects. It is unclear if nebulized eucalyptus oil is beneficial for prevention of complications associated with endotracheal intubation. Details: A small clinical study in Iranian patients intubated and receiving care in the intensive care unit shows that nebulizing 4 mL of eucalyptus 5% oil in 6 mL of normal saline every 8 hours for 3 days increases oxygen saturation and decreases peak inspiratory pressure, but does not affect the level of consciousness as measured using the Glasgow Coma Scale, when compared with nebulized normal saline (110096).
• Fever. Inhaled eucalyptus oil has only been evaluated in combination with other ingredients for fever following vaccination; its effect when used alone is unclear. Details: A large clinical study in adults shows that inhaling aromatherapy with eucalyptus oil 0.05 mL in combination with topical application of tea tree oil 0.05 mL on the affected arm every 2 hours while awake for 3 days after COVID-19 vaccination reduces the frequency of self-reported fever when compared with control during the first 48 hours after vaccination (113141). The interpretation of these results is limited by baseline group differences in receipt of various COVID-19 vaccine products, which may differ in side effect frequency. Also, it is unclear if these effects are due to eucalyptus, tea tree oil, or the combination.
• Genital herpes. Although there is interest in using topical eucalyptus for genital herpes, there is insufficient reliable information about the clinical effects of eucalyptus for this condition.
• Gingivitis. Using chewing gum containing eucalyptus extract might improve gingivitis. Details: Preliminary clinical research shows that chewing gum containing 0.4% to 0.6% eucalyptus extract five times daily for 4 days improves gingivitis when compared with placebo (92863).
• Gonorrhea. Although there is interest in using oral eucalyptus for gonorrhea, there is insufficient reliable information about the clinical effects of eucalyptus for this condition.
• Halitosis. Using chewing gum containing eucalyptus extract might improve halitosis. Details: Preliminary clinical research shows that chewing gum containing 0.4% to 0.6% eucalyptus extract five times daily for 12 weeks significantly improves halitosis and coating of the tongue when compared with placebo (92863).
• Headache. Topical eucalyptus has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that applying a combination of peppermint oil, eucalyptus oil, and ethanol topically to the forehead and temples does not affect headache pain, but improves cognitive performance and produces relaxation, when compared with placebo (3801).
• Influenza. Although there is interest in using oral or inhaled eucalyptus for influenza, there is insufficient reliable information about the clinical effects of eucalyptus for this condition.
• Injection site reaction. Inhaled eucalyptus oil has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A large clinical study in adults shows that inhaling aromatherapy with eucalyptus oil 0.05 mL in combination with topical application of tea tree oil 0.05 mL on the affected arm every 2 hours while awake for 3 days after COVID-19 vaccination improves self-reported muscle ache, localized swelling, pain, and fever, but not erythema, joint pain, or headache when compared with control in the first 24 hours after vaccination. However, at 24-48 hours, only localized swelling and fever were improved in the group using eucalyptus and tea tree oil (113141). The interpretation of these results is limited by baseline group differences in receipt of various COVID-19 vaccine products, which may differ in side effect frequency. Also, it is unclear if these effects are due to eucalyptus, tea tree oil, or the combination.
• Lice. Topical eucalyptus oil has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research in patients with head lice shows that applying eucalyptus oil 11% and lemon tea tree oil 1% (MOOV Head Lice Solution, Ego Pharmaceuticals Pty Ltd.) reduces the ex-vivo egg hatching rate by only 3%, compared with a 44% reduction with tea tree oil and lavender oil (NeutraLice Natural Lotion), and a 68% reduction with benzyl alcohol, mineral oil, and triethanolamine (NeutraLice Advance) (19188). However, other research in elementary school aged children shows that applying the MOOV Head Lice Solution combination product to the scalp for 10 minutes, once weekly for 3 weeks, is more effective than applying pyrethrins and piperonyl butoxide once weekly for 2 weeks. At 7 days after the last application, 71% of children treated with the eucalyptus formulation were still free of lice, compared with 33% of children in the control group (98492).
• Onychomycosis. Although there is interest in using topical eucalyptus for onychomycosis, there is insufficient reliable information about the clinical effects of eucalyptus for this condition.
• Oral mucositis. Although there is interest in using topical or oral eucalyptus for oral mucositis, there is insufficient reliable information about the clinical effects of eucalyptus for this condition.
• Osteoarthritis. Although there is interest in using topical eucalyptus for osteoarthritis, there is insufficient reliable information about the clinical effects of eucalyptus for this condition.
• Rheumatoid arthritis (RA). It is unclear if inhaled eucalyptus oil is beneficial in patients with RA. Details: A small clinical study in patients with RA shows that aromatherapy with eucalyptus essential oil, delivered by applying 2 mL of oil to pads attached to clothing for 5 minutes three times daily for 1 month, reduces pain and improves quality of life when compared with placebo (110094).
• Rhinosinusitis. Although there is interest in using inhaled eucalyptus for rhinosinusitis, there is insufficient reliable information about the clinical effects of eucalyptus for this condition.
• Tinea corporis. Although there is interest in using topical eucalyptus for tinea corporis, there is insufficient reliable information about the clinical effects of eucalyptus for this condition.
• Tuberculosis. Although there is interest in using oral eucalyptus for tuberculosis, there is insufficient reliable information about the clinical effects of eucalyptus for this condition.
• Ventilator-associated pneumonia (VAP). It is unclear if eucalyptus is beneficial for the prevention of VAP. Details: Preliminary clinical research in ventilated adult patients shows that nebulizing a 2% eucalyptus solution for about 20 minutes every 8 hours reduces the incidence of late bacterial pneumonia (occurring more than 96 hours after initiation of ventilation) from 58% to 30% when compared with placebo. In those patients who developed VAP, the onset occurred approximately 3 days later, on average, in the eucalyptus group than in the placebo group (104958).
• Wound healing. Although there is interest in using topical eucalyptus for wound healing, there is insufficient reliable information about the clinical effects of eucalyptus for this condition. More evidence is needed to rate eucalyptus for these uses.

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POSSIBLY SAFE ...when used topically in low concentrations, short-term. Concentrations ranging from 0.1% to 11% seem to be safe for short-term application to intact skin (272,10327,89893). ...when used by inhalation, appropriately. Even relatively dilute concentrations of camphor can irritate the nose and sinuses. However, it is difficult to determine a safe concentration of inhaled camphor. The Occupational Safety and Health Administration (OSHA) has set a permissible workplace air exposure to synthetic camphor of no more than 2 parts per million (ppm) (272,105033). It is unclear how this correlates to the exposure obtained from a camphor balm or steam bath.

LIKELY UNSAFE ...when used topically on broken or injured skin. Application of camphor to broken skin can result in systemic absorption and toxicity (272). ...when inhaled in large concentrations, which can result in systemic toxicity (13445,39666). However, it is difficult to determine a safe concentration of inhaled camphor. The National Institute for Occupational Safety and Health (NIOSH) has determined an Immediately Dangerous to Life or Health Concentration (IDLH) of synthetic camphor in workplace air to be 200 ppm (105033). It is unclear how this correlates to the exposure obtained from a camphor balm or steam bath.

UNSAFE ...when used orally. Although a particular oral product containing camphor and hawthorn (Korodin Herz-Kreislauf-Tropfen) has been used safely by adults in some clinical studies (103620), ingestion of camphor can cause significant toxicity, including death (13442). Oral preparations of camphor are no longer available in the US (13442).

CHILDREN: POSSIBLY UNSAFE
when used topically (4814). Young children might be more susceptible to the adverse effects associated with even minor systemic absorption of camphor. The American Academy of Pediatrics recommends that camphor not be used in treating children (4814).

CHILDREN: UNSAFE
when used orally. Ingestion of camphor can cause significant toxicity including death (4814). The American Academy of Pediatrics recommends that available non-prescription topical camphor products should not exceed 11% strength to limit toxicity if accidentally ingested by children (4814).

PREGNANCY AND LACTATION: UNSAFE
when used orally. Ingestion of camphor can cause serious toxicity including death (13442). There is insufficient reliable information available about the safety of using camphor topically during pregnancy and lactation.

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LIKELY SAFE ...when used orally in amounts commonly found in foods. Eucalyptus has Generally Recognized As Safe status (GRAS) for use in foods as a flavoring in the US (4912).

POSSIBLY SAFE ...when eucalyptol, a constituent of eucalyptus oil, is used orally and appropriately. Eucalyptol appears to be safe for up to 12 weeks (13302).

POSSIBLY UNSAFE ...when the undiluted oil is used topically. Prolonged or widespread exposure has caused neurotoxicity (12869). There is insufficient reliable information available about the safety of diluted eucalyptus oil when used topically.

LIKELY UNSAFE ...when the undiluted oil is ingested orally. Ingesting 3.5 mL of undiluted oil can be fatal in adults (12867). There is insufficient reliable information available about the safety of eucalyptus oil when inhaled as aromatherapy or when eucalyptus leaf is used orally in medicinal amounts.

CHILDREN: LIKELY SAFE
when used orally in amounts commonly found in foods. Eucalyptus has Generally Recognized As Safe (GRAS) status for use in foods in the US (4912).

CHILDREN: LIKELY UNSAFE
when eucalyptus oil is used orally (12867,49002,107493,107495). ...when eucalyptus oil is used topically in infants and young children. There are reports of neurotoxicity in infants and young children exposed to topical eucalyptus oil. In one of these cases, a 12-month-old child was bathed in water containing eucalyptus oil and other essential oils; in another case, a child had a dressing containing eucalyptus oil applied every 2-4 hours daily for 2 days (12868,12869). ...when eucalyptus solutions are inhaled using a vaporizer (49002).

PREGNANCY AND LACTATION: LIKELY SAFE
when used orally in amounts commonly found in foods (4912). There is insufficient reliable information available about the safety of medicinal amounts of eucalyptus oil; avoid using.

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HEPATOTOXIC DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use of camphor with other hepatotoxic drugs might increase the risk of liver damage.  Details There have been a few case reports of transient elevations in liver enzymes in adults after oral or topical use of camphor (39576,97260). There has also been one case of hepatotoxicity in an infant after topical camphor use (4608).

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AMPHETAMINES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, inhaling eucalyptol may reduce the effectiveness of amphetamines.  Details Animal research suggests that inhaling eucalyptol may reduce the levels of amphetamines in the blood (48987).

ANTIDIABETES DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, eucalyptus leaf might increase the risk of hypoglycemia.  Details Animal research suggests that eucalyptus leaf might have hypoglycemic activity, and might have additive effects when used with antidiabetes drugs (12871).

CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, eucalyptus might increase the levels of CYP1A2 substrates.  Details In vitro research suggests that eucalyptus oil might inhibit CYP1A2, although this has not been reported in humans (12479).

CYTOCHROME P450 2C19 (CYP2C19) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, eucalyptus might increase the levels of CYP2C19 substrates.  Details In vitro research suggests that eucalyptus oil might inhibit CYP2C19, although this has not been reported in humans (12479).

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, eucalyptus might increase the levels of CYP2C9 substrates.  Details In vitro research suggests that eucalyptus oil might inhibit CYP2C9, although this has not been reported in humans (12479).

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, eucalyptus might increase the levels of CYP3A4 substrates.  Details In vitro research suggests that eucalyptus oil might inhibit CYP3A4, although this has not been reported in humans (12479).

PENTOBARBITAL (Nembutal) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, inhaling eucalyptol might reduce the effectiveness of pentobarbital.  Details Animal research suggests that inhaling eucalyptol reduces the level of pentobarbital that reaches the brain (48987).

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General ...Orally, camphor is unsafe and can cause significant toxicity. Topically and by inhalation, camphor seems to be generally well-tolerated.
Most Common Adverse Effects:
Oral: Gastrointestinal and ocular symptoms of toxicity can occur within 5-90 minutes of ingestion. Neurological symptoms can occur with ingestion of quantities greater than 50 mg/kg.
Topically: Dermatitis and skin irritation.
Inhalation: Nose and sinus irritation.
Serious Adverse Effects (Rare):
All routes: Systemically absorbed camphor can lead to seizures, respiratory depression, coma, and death.

Cardiovascular ...Case reports of intoxication due to accidental or intentional consumption have included peripheral circulatory shock and sinus tachycardia (39649,97261). A 54-year-old female with a history of cardiomyopathy and atrial fibrillation developed several episodes of ventricular tachycardia and fibrillation requiring use of a defibrillator after ingestion of Vicks VapoRub, containing 4.8% camphor. She had been taking 7.5 grams of the product weekly, and took an additional 150 grams the week prior to admission. After discontinuing all camphor-containing products and receiving supportive measures, the patient's symptoms and laboratory abnormalities returned to normal (97260).

Dermatologic ...Orally, camphor can cause significant toxicity. In more severe toxicity, general pallor and cyanosis of the lips occur (13442,13444). Topically, camphor is not as likely to cause adverse effects. But some amount of camphor can be absorbed through intact skin. Topical use of camphor has been associated with contact eczema (13445).
Warn patients not to heat products such as Vicks VapoRub in the microwave. Serious burns have occurred when the product is superheated in the microwave (13446).

Gastrointestinal ...Orally, camphor can cause significant toxicity. Symptoms of camphor toxicity occur rapidly within 5-90 minutes of ingestion. Burning of the mouth and throat, and nausea and vomiting are the first symptoms (13442,13444,39589,39626,39646,39658).

Hepatic ...Orally, camphor can cause transient elevations of liver enzymes in both adults and children. There is also a report of increased liver enzymes in an infant who received a camphor-containing topical cold remedy. The enzymes affected included aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase, and lactate dehydrogenase (LDH). The liver enzymes normalized after stopping the topical cold formula (4608).There is also a report of increased liver enzymes in a 35-year-old adult following "coining" with a balm containing camphor, which involves applying the balm and then rubbing the area with a coin until ecchymosis. The liver enzymes normalized after stopping treatment (39576). Elevated liver enzymes were also reported in a 54-year-old female after oral ingestion of Vicks VapoRub, containing 4.8% camphor. She had been taking 7.5 grams of the product weekly, and took an additional 150 grams the week prior to admission. After discontinuing all camphor-containing products and receiving supportive measures, the patient's symptoms and laboratory abnormalities returned to normal (97260).

Neurologic/CNS ...Orally, camphor can cause significant toxicity. Neurological symptoms occur with ingestion of greater than 50 mg/kg. These symptoms include irritability, exaggerated tendon reflexes, tonic muscular contraction, myoclonic jerks, seizures, confusion, coma, and apnea. Seizures are sometimes the first manifestation of serious toxicity (13442,13444,39560,39589,39629,39646,39649,39658,39660). In children under 6 years of age, doses as low as 700-800 mg, and possibly as low as 500 mg, have caused serious seizures, resulting in respiratory failure and death (13442,13444,39589). Asymptomatic patients who have ingested camphor should be observed for at least 3 hours in a hospital. A 12-hour observation period may be prudent as seizures have occurred 9 hours after ingestion in apparently recovering patients. In patients who survive, symptoms usually resolve within 24 hours, although there are reports of persistent abnormalities for days to weeks. Long-term sequelae have not been reported after resolution of symptoms (13442,13443). In one case, a 10-year-old boy who intentionally ingested cold remedy transdermal patches containing a total of camphor 300 mg experienced mental status changes and tremulousness (39626).
Topically, camphor is not as likely to cause adverse effects, but small amounts can be absorbed through intact skin. A considerable amount of camphor can also be absorbed when inhaled. Excessive use of camphor, either topically or by inhalation, can result in the development of systemic toxicity (13445,39666). Topically and by inhalation, camphor has been associated with the occurrence of seizures. In one prospective observational study, there were 20 reports of new onset seizures and 29 reports of recurrent seizures in adults and children after use of camphor, either alone or in combination with eucalyptus oil. Most cases of seizure with topical use occurred 0.5-24 hours after topical application to the chest, neck, or face. Most cases of seizure with inhalation occurred about 2-30 minutes after steam inhalation of camphor (105028).

Ocular/Otic ...Orally, camphor can cause significant toxicity. Ocular symptoms such as mydriasis and darkening of vision may occur (13442,13444). There is a case report of blurry vision following accidental ingestion of camphor (39667).
There is a case report of self-inflicted conjunctival inflammation after using camphor in the eyes (39624). Warn patients not to heat products such as Vicks VapoRub in the microwave. Eye injury has occurred when the product is superheated in the microwave (13446).

Pulmonary/Respiratory ...When inhaled in large enough concentrations, camphor can irritate the nose and sinuses. However, it is difficult to determine a safe concentration of inhaled camphor (105033).
A 54-year-old females with a history of asthma developed shortness of breath, hypoxemia, and respiratory acidosis after oral ingestion of Vicks VapoRub, containing 4.8% camphor. She had been taking 7.5 grams of the product weekly, and took an additional 150 grams the week prior to admission. After discontinuing all camphor-containing products and receiving supportive measures, the patient's symptoms and laboratory abnormalities returned to normal (97260).

Other ...A smell of camphor from the breath and body have been reported following oral intake of camphor (39560,39589,97261).

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General ...Orally, diluted eucalyptus oil is generally well tolerated, but the undiluted oil can cause toxicity.
Most Common Adverse Effects:
Orally: Diarrhea, nausea, vomiting.
Topically: Burning, itching, redness, stinging.
Serious Adverse Effects (Rare):
Orally: Signs of toxicity can occur with the undiluted oil at doses as low as 1 mL and include central nervous system depression, shallow respiration, rapid pulse, apnea, coma, and death.
Topically: Prolonged exposure or large amounts of eucalyptus oil can cause agitation, ataxia, drowsiness, muscle weakness, seizures, and slurred speech. The risk of toxicity may be greater in children.
Inhalation (as aromatherapy): Seizures.

Cardiovascular ...Orally, one case of premature ventricular contractions has been reported in a previously healthy 29-year-old male who ingested approximately one ounce of eucalyptus oil (48983).

Dermatologic ...Topically, eucalyptus pollen, leaves, oil, and the constituent eucalyptol can cause contact dermatitis in sensitive people (13303,48931,92856,92858,92859,98497). In some cases, symptoms respond to treatment with topical corticosteroids and tacrolimus (92856). In one case report, transient local redness, burning, and irritation was reported in a 4-year-old child who was bathed in water containing eucalyptus oil. The symptoms resolved within one hour of rinsing the skin with clear water (48983). In a clinical study, treatment with a combination of eucalyptus oil and lemon tea tree oil caused burning, redness, itching, or stinging in up to 20% of the patients. Stinging usually resolved within 10 minutes of application and redness within 30 minutes (19188,98492).

Gastrointestinal ...Orally, eucalyptus oil can cause nausea, vomiting, and diarrhea (48983,48993,48995). Abdominal pain has been reported in a trial of the eucalyptus constituent eucalyptol for inflammatory bowel disease (IBD) (48936).

Immunologic ...A case of IgE-mediated exacerbation of asthma and rhinitis symptoms has been reported in a patient who consumed eucalyptus. Similar worsening of symptoms occurred when the patient inhaled eucalyptus pollen (48957).
Occupational exposure to eucalyptus may cause allergic dermatitis (98497).

Neurologic/CNS ...Orally, eucalyptus oil can cause central nervous system depression, coma, and status epilepticus (12867,48946,48983).
Topically, orally, and by inhalation, eucalyptus oil has been associated with seizures. A systematic review describes the characteristics of 49 children and 61 adults with seizures associated with various routes of administration. Patients with no seizure history were classified as a eucalyptus oil-induced seizure (EOIS), while patients with a history of seizure or susceptibility to seizure were defined as a eucalyptus oil-provoked seizure (EOPS). In EOIS cases, topical use was reported in 74%, inhalation in 22.5%, and ingestion in 3.5%; for EOPS cases, topical use was reported in 79%, inhalation in 16%, and ingestion in 5%. Generalized tonic-clonic seizures are the most prominent type of seizure in EOIS cases (96%). Among EOPS patients, 37% had focal onset motor seizures with impaired awareness, 24% had focal onset aware motor seizures, 13% had focal to bilateral tonic-clonic seizures, and 26% had generalized onset tonic-clonic seizures (107494). One prospective observational study that was included in this systematic review provided additional details on eucalyptus-induced seizures. This study included 18 reports of EOIS and 28 reports of EOPS in adults and children after topical or inhaled use of eucalyptus oil, either alone or in combination with camphor. The time to seizure onset was 0.5-48 hours after topical application, 2-30 minutes after inhalation, and 0.5-6 hours after ingestion. (105028).
One prospective observational study and one case series have described 20 case reports of seizures occurring in children after ingestion of eucalyptus oil. Most of these seizures are generalized tonic-clonic in nature, occur 15-30 minutes after exposure, and do not reoccur following the discontinuation of eucalyptus oil. Seizures have been reported with both overdoses and therapeutic doses (107493,107495) and include cases of both EOIS and EOPS (107495). Additionally, children appear more likely to require intensive care and mechanical ventilation when compared with adult cases (107494).
A case of fever and headache has been reported in a patient who routinely applied a teaspoon of gel containing eucalyptus extract in his throat or nose to treat sore throat or rhinitis (48946).

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