Article co-authored by Stéphanie Monnatte-Lassus Aromatologist, Plantar Reflexologist and Relaxologist and Joëlle le Guehennec, President of the EAI, French School of Integrative Aromatherapy.

Pregnant women (less than 3 to 5 months) or breastfeeding and children (less than 6 years old) must in principle, take the precaution of contacting a professional. Some essential oils are abortive, uterotonic or toxic to babies.

People suffering from certain pathologies must be very vigilant about the use of an essential oil and seek professional advice:

• Respiratory allergies and asthma
• Allergy to: camphor, cortisone, aspirin
• Hormone-dependent cancer
• Epilepsy or epileptic ground
• Hyperestrogenia
• Hypertension or hypotension
• Hyperthyroidism or hypothyroidism
• Hepatic insufficiency
• Insuffisance rénale
• Mastose (= affection du sein)
• Phlebitis
• Specify when anticoagulant or hormonal treatment is in progress

In addition, some essential oils should require vigilance by their possible toxicity. Indeed, the side effects potentials are numerous:

• Abortif
• Hepatotoxic
• Irritant
• Nephrotoxic (= kidney toxicity)
• Neurotoxique
• Skin and mucous membranes: dermotoxicity, allergies, hypersensitivity, irritations, photosensitization …
• Narcotic in high doses
• tachycardia
• Vomiting, etc.

The toxicity of an essential oil can appear a few minutes after its use (acute toxicity), after a few months of use, and sometimes after one or more years (by cumulative effects).