Essential Oils, Diffusers and Breathing Problems
What asthma organizations, agencies and the few studies we could read say about essential oils, diffusers and scented products for people with asthma or other breathing problems.
Content last updated . This page has not been medically reviewed.
Safety first. Supplements can cause side effects and interact with medicines. Read mushroom safety and interactions before you use any mushroom product.
Urgent first
Call 911 if breathing becomes difficult, the throat or tongue swells, or an asthma attack is not settling. The NHS (UK) says an asthma attack, with severe symptoms and difficulty breathing, can be life-threatening. [1] Poison Control says any allergic reaction that includes difficulty breathing should be treated as a medical emergency. [2] If an oil was swallowed or choked on, call Poison Help at 1-800-222-1222, because aspirating an essential oil can cause pneumonia. [2]The short answer
We did not find a trial or a guideline that tests whether diffusing essential oils helps or harms people with asthma. Proper evidence not found for that specific question. We searched PubMed for essential oil diffusers and asthma and read pages from the NHS, the Asthma and Allergy Foundation of America (AAFA), the US Environmental Protection Agency (EPA), Poison Control and the NCCIH. What we did find is that strong scents are listed as possible irritants for sensitive airways, and a small amount of research on what diffusers release. Whether a given person reacts depends on that person, so ask the doctor who manages the asthma.What asthma and environmental sources say
| Source | What it says | What it does not say |
|---|---|---|
| AAFA (US patient organization) | Lists strong fumes, vapors or odors, such as perfumes and scented soaps, among irritants. It says they can bother inflamed, sensitive airways. [3] | It does not name essential oils or diffusers in the text we read. |
| EPA (US) | Says asthma may be worse around products such as cleaners, paints, cosmetics or air fresheners. [4] | It does not name essential oil diffusers. |
| NHS (UK) | Lists asthma triggers such as exercise, high levels of air pollution, cold air and contact with something a person is allergic to. [1] | No mention of essential oils in the text we read. |
| Poison Control (US) | Says vaporizer products with essential oils, usually camphor, are usually safe when used as directed. [2] | It does not say they are safe for everyone with asthma. |
| An aromatherapy association (NAHA, US) | Says inhalation presents a very low level of risk to most people. [5] | "Most people" is not a statement about people with asthma. |
What research found
| Question | What the source found | Strength of evidence |
|---|---|---|
| Do plant scent compounds relate to asthma symptoms? | In a study of 14 volunteers with seasonal asthma, higher levels of pinene, camphor, linalool and linalyl acetate in outdoor air predicted respiratory symptoms. [6] | Preliminary. Small, observational, outdoor air from plants, not diffusers or measured oil use. |
| What does a diffuser put in the air? | A chamber study of an ultrasonic diffuser used with lemon, lavender, eucalyptus and grapeseed oils measured emitted compounds and particles. [7] The authors' modeling suggests reasonable use can add substantially to fine particles indoors. [7] | Laboratory measurement. It measured air, not breathing or symptoms in people. |
| Is a longer exposure a concern? | NAHA, quoting two aromatherapy authors, says the likely risk would be prolonged exposure to relatively high vapor levels, which could cause headaches, vertigo, nausea and lethargy. [5] | Expert opinion, not a trial. |
The study of people with asthma measured outdoor air, so it cannot tell us what a living-room diffuser does. The chamber study measured air, not health. Neither shows that a particular oil is safe or unsafe for a person with asthma.
Practical points that sources support
- AAFA lists strong odors as possible irritants of inflamed airways. [3] Ask the doctor who manages the asthma which exposures to avoid.
- The EPA advises increasing ventilation when using products that emit volatile organic compounds. [8] Essential oils release such compounds, as the chamber study shows. [7]
- Reed diffuser liquid is an essential oil dissolved in rubbing alcohol and must be kept out of the reach of children. [2]
- Menthol and camphor products near babies have their own cautions: see babies and children.
- Do not stop or change a prescribed asthma medicine because of a scent or an oil. Ask the prescriber or pharmacist.
Frequently asked questions
Can an essential oil diffuser trigger asthma?
Sources list strong fumes and odors as possible irritants for sensitive airways. [3] We did not find a study testing diffusers in people with asthma.
Are essential oils a treatment for asthma?
Proper evidence not found in the sources we read. Do not replace asthma medicine with an oil. Ask the prescriber or pharmacist.
What should I do if breathing gets hard after smelling an oil?
If breathing is difficult or the throat feels tight, call 911. [2] [9]
Do children with asthma need extra care?
The EPA says a child's asthma may be worse around products such as air fresheners and cosmetics. [4] Ask the child's doctor.
Are vaporizer products safe?
Poison Control says vaporizer products with essential oils (usually camphor) are usually safe when used as directed. [2]
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
Limits and uncertainty
- Oils differ. A finding about camphor or pinene does not transfer to lavender or orange.
- We did not find a study in which people with asthma were exposed to a diffuser and followed for symptoms.
- Asthma organizations in the sources we read speak about scents in general, not essential oils.
See also how diffusers work and their cautions, indoor air quality and exposure and claims about essential oils for asthma and allergies.
References
- Asthma, NHS (UK). Read 2026-10-23.
- Essential oils: Poisonous when misused, Poison Control (US). Read 2026-10-23.
- What Triggers or Causes Asthma?, Asthma and Allergy Foundation of America (US patient organization). Read 2026-10-23.
- Asthma Triggers: Gain Control, US Environmental Protection Agency. Read 2026-10-23.
- Safety, National Association for Holistic Aromatherapy (NAHA, US professional association); page undated; the eye-safety section is an article by the aromatherapy educator Robert Tisserand. Read 2026-10-23.
- Essential oils, asthma, thunderstorms, and plant gases: a prospective study of respiratory response to ambient biogenic volatile organic compounds (BVOCs), Gibbs JE, J Asthma Allergy 2019, PMID 31417289. Read 2026-10-23.
- Volatile organic compound and particulate matter emissions from an ultrasonic essential oil diffuser, Schwartz-Narbonne H et al., Indoor Air 2021, PMID 33905580. Read 2026-10-23.
- Volatile Organic Compounds' Impact on Indoor Air Quality, US Environmental Protection Agency. Read 2026-10-23.
- Anaphylaxis, NHS (UK). Read 2026-10-23.
Education, not medical advice. This page is for general information. It does not diagnose or treat any condition and is not a substitute for care from a qualified health professional. Natural does not automatically mean safe. Ask a clinician or pharmacist before changing your care, especially if you take medication, are pregnant or breastfeeding, or have a health condition.