Oregano, tarragon, savory cinnamon, clove and thyme oils all contain phenols. Citronella, Limonene, Linacool all have flea repellant properties and are sometimes offered in flea preparations. They are quite safe for dogs because they can process them in the liver. They are much more toxic for cats and in lower doses.
Being too sensitive to essential oils, and the fact they lick themselves so much,. Applying this during a bath or as a spray does not change a cats internal Ph.
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