Insomnia can be a symptom of severe estrogen deprivation - which is what the aromasin does (aromasin stops you from making estrogen, whereas the arimidex just stops certain parts of the body - including cancer - from being able to use the estrogen.)
For some women aromasin does seem to greatly affect their ability to sleep regardless of how long they have been on it (I was up almost all night after only my 2nd dose.)
If the dr thinks the arimidex will still give you adequate protection, I would switch back.
Using some weak phytoestrogens in your diet can help alleviate the symptoms of estrogen deprivation, without feeding any existing cancer cells. Very small amounts of ground flax seed (1 - 2 tsp/day) mixed with cottage cheese is a good start. Stay away from soy of any kind - it is a strong phytoestrogen and will feed cancer cells. Bioflavinoids are good, either in supplement form (rutin and quercetin or isoquercetin, grape seed extract) or foods (dark chocolate - at least 70% cacao, green or black tea, citrus fruit - the sugar in these is not harmful as far as feeding the cancer, buckwheat, onions, garlic, red wine - not more than 2 - 4 ounces per day of a table wine rather than a beverage wine.)
Should you decide to stop the anti-estrogen drugs altogether, there are still MANY things you can do to keep any cancer cells from getting the estrogen they need to grow. When diagnosed with metastatic breast cancer earlier this year, I was unable to take the anti-estrogen drugs - they make me very ill. So having had prior medical knowledge thru nursing, I researched the problem and designed my own natural cancer regimen. (I do not recommend people without prior medical experience do this by themselves, but rather seek the advise of a professional holistic practitioner.) I have little in the way of finances to spend on herbs and supplements, so I put together a low cost routine that is full of natural aromatase inhibitors (which is what Aromasin does) and weak phytoestrogens that act as estrogen blockers (which is what Arimidex and Tamoxifen do) plus natural cancer killers. I was able to put my metastasis in remission within a few months. I do not offer my regimen as a prescription for anyone as I am not a dr and my regimen is designed specifically for my needs, but I have published it so that others can get an idea of very simple herbs, supplements and foods that are effective cancer fighters - I have made note of those things that should be safe for most people to use. You are welcome to take a look at anything else on the blog that interests you:
http://motherearthtreasurechest.blogspot.com/2008/09/my-pers
You can also get excellent information on using naturals to prevent recurrence of cancer:
www.cancertutor.com
www.lefcancer.org
Please let me know if you have questions or think I can be of assistance to you.
Sincerely,
Tre