Saturday night I got home late and my dog didn't recognize me. Being a nanny I thought I woke him up and he was having a night terror. Sunday, he was still acting weird. I realized that I had been running my new diffuser and decided to turn it off. Sunday afternoon, he was feeling better.Today at work, my dog sitter said that he wouldn't come out from under the bed. It was very odd as he is a happy dog.I came from work early and again, he was very confused about who I was.So I took him to emergency vet.It turns out that the tea tree oil I was using in the diffuser is toxic for dogs. Thankfully the test showed that his liver was ok but we weren't out of the woods yet. He was given fluids under his skin to get the toxins out.The vet and the poison control are saying that they see these cases often now that the popularity of essential oil is growing.Please make sure that the essential oils you are burning are not toxic for your pets.Here is a list of essential oils not to use if you have a dog at homeAnise (Pimpinella anisum)Birch (Betula)Bitter Almond (Prunus dulcis)Boldo (Peumus boldus)Calamus (Acorus calamus)Camphor (Cinnamomum camphora)Cassia (Cassia fistula)Chenopodium (Chenopodium album)Cloves (Syzygium aromaticum)Garlic (Allium sativum)Goosefoot (Chenopodium murale)Horseradish (Armoracia rusticana)Hyssop (Hyssopus sp. with the exception of Decumbens)Juniper (Juniperus sp. with the exception of Juniper Berry)Mugwort (Artemisia vulgaris)Mustard (Brassica juncea)Oregano (Origanum vulgare)Pennyroyal (Mentha pulegium)Red or White ThymeRue (Ruta graveolens)Santolina (Santolina chamaecyparissus)Sassafras (Sassafras albidum)Savory (Satureja)Tansy (Tanacetum vulgare)Tea Tree Oil (Melaleuca alternifolia)Terebinth (Pistacia palaestina)Thuja (Thuja occidentalis)Wintergreen (Gaultheria procumbens)Wormwood (Artemisia absinthium)Yarrow (Achillea millefolium)