Hi Spiderman,
I really don't want to douse your spirits but to be totally honest and realistic, I believe you will find that if you have been diagnosed with epilepsy, you will not be accepted into any branch of the UK armed forces, regardless of whether or not you take controlling medication. When I was serving I came across a few people that were medically discharged after developing epilepsy during service or it was found out they had experienced epileptic seizures prior to service and had failed to declare it (they were binned for the medical reason not the dishonesty).
You do, however, raise a question mark over the diagnosis. I reckon this should be your initial focus. Establish beyond any doubt whatsoever whether or not you have had epileptic seizures or whether the seizures were the result of other factors, e.g. CO poisoning, as you mentioned. If it is decided that you do / did not have epilepsy make sure you get consultants reports and that these are placed on your medical records. You may probably have to do this privately so get ready for the costs.
The next thing to do, assuming the military career is out of the picture, is to print off the JAA Class 1 Medical Visual Standards and trot off to your local optometrist and get him/her to verify that you meet the standards. Check Class 2 standards at the same time - at least then you'll know if you can fly for recreational purposes. I can recommend a good one in South Wales who is also a PPL. The link to the standards is below:
http://www.caa.co.uk/srg/med/document.asp?groupid=211
Once you've done all of this, get on the telephone to CAA Medical Branch and talk to them. They are very helpful and will advise you properly.
I do know what medical hiccups can be like as I'm having a ding dong with the FAA at the moment over dizziness I experienced a few years back when taking shedloads of analgesics following a bad accident. Guess what the side effects of the meds were? Oh, yes, dizziness, nausea, visual disturbances, etc. all of which I had, and guess what happened when I came off the meds - yip, all the ugly side effects went away, but will they accept that, no! I'm having to go through specialist vestibular testing, which is taking a lot of time and, as I'm having to do it privately, is costing plenty of cash. It's a pain but they hold the trump cards and I've just got to go along with it, pay up and get the reports.
Hope this helps,
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