Hi Ellie
I have Bipolar II, and get regular aromatherapy treatments. I mainly get massages when my mood is hypomanic because a symptom is an increased need for human touch, and at times I've had 3 treatments a week, especially over the Winter.
The oils that are used on me depend on what phase of bipolar I am going through. The oil which is I seem to respond to the best is Bergamot - which is wonderfully grounding. He tends to use a lot of citrus on me - lemon and lime - neither of which I like, and he can only add them if he doesn't tell me. Clary Sage is fabulous for low mood. We stayed on Bergamot and Lavender for a long while, when I was having a rough time. That worked quite well when I was fragile, I'd just go home afterwards in a cloud and sleep.
If the person is using medication they tend to be either/and/or mood stabilisers, antidepressants, antipsychotics. It depends on what type of bipolar they have, and the degree of severity. My GP thinks it's all codswallop anyway (complementary medicine) - so when I told her I was getting aromatherapy massages she just said 'that's nice'. But then I'm no longer on medication so she'd not be worried about interactions. My masseur got me to sign the regular disclaimer form, and left it to me to tell my GP. We play it by ear, and he takes feedback from every session. He's on Facebook, so I send him a message there with an update.
The only oil I've had trouble with is Frankincense. It gave me terrible racing heart and feelings of doom. But, that may have nothing to do with bipolar, it may be my unique physiology.
Ava x