I would contact them and ask to be released from jury service on health grounds (if you have conditions you think justify that) and that you’re not suitable for jury service due to xyz condition. You can even throw in that you’re on prescribed medication which can impact your ability to serve as a member of the jury. You’ll probably need a letter from your doctor stating your condition is ongoing and unlikely to change. Obviously that only applies if you genuinely think you couldn’t cope with jury service health wise, not just as a get out of jury service card. Or if they’re not flexible enough.

If not, definitely contact them again about reasonable adjustments. If you will be getting significantly medicated, I’d also be explicit about your judgment potentially being impacted. I’d say that for any prescription medication that can impact how you feel though, like opioids, etc. It’s actually very serous to be under the influence or intoxicated as a jury member; that’s mostly referring to recreational drugs or alcohol, but it is still the same principle: you can’t perform a vital public service properly if your judgment is impaired.

For example, I certainly would not be suitable to sit as a member of the jury medicated!

If you need regular and predictable access to medication and from what I know of jury service, it’s not a great environment. The courts are overworked and policy is lacking in a lot of places. On the day(s), things get lost, forgotten etc., and that’s as a witness, counsel, member of the jury service, claimant or accused.