If you are taking homeopathic remedies do not use black pepper, camphor, eucalyptus, peppermint, rosemary, or spearmint.
Hydrosols are usually used by spraying for things like air fresheners, deodorant or body spray .
There are many safe oils that are helpful in reducing high blood pressure. Among them are: Bergamot, Lemon, Melissa, Neroli/Orange Blossom, Orange, and Yarrow
There are many other safe oils that can be very helpful for diabetes. Among them are: Sweet Birch, Cinnamon, Clove Bud, Eucalyptus and Ylang Ylang.
Among those to stay away from if you have epilepsy are: Camphor, eucalyptus, fennel, hyssop, rosemary, spike lavender (Lavandula latifolia) and sage. There are also oils that calm epilepsy attacks like Mandarin/Tangerine.