Antihistamines alone tend not to have a severe withdrawal - but all people are different and you were using them for some time. So this certainly could be the cause.
I think it was the Mirtazapine, even at that low dose, because taking 1mg again a few nights ago fixed a lot of the symptoms.
The other is stressful life events (even if they don't seem to be bothering you - psychosomatic presentations with psychic anxiety over the symptoms is quite common) or withdrawal from methylphenidate (you mentioned having used it in the past - recently?). Anything else you stopped recently?
Nope .. nothing else, and I don't think I mentioned methylphenidate? I haven't been on that in 4 years. Life stressors are about the same as always, though the akathisia itself is driving me crazy.
St. Johns wart's efficacy is debatable and it will take time to work. It could worsen the symptoms in the short term.
Yeah, that was a dumb idea, I was just extremely desperate..
A Benzo will calm you down no doubt but if it can be avoided go for it. I'd advise you re-start the antihistamines at the usual dosage and if symptoms disappear we have a good idea its either withdrawal from them or anxiety. Then reduce the dose slowly and if you have had any life events you can tackle them.
I react paradoxically to benzodiazepines anyway. As I mentioned, reinstating a tiny dose of Mirtazapine fixed the akathisia. But I was withdrawing from like 1-3mg anyway, so it seems like I'll have to face the withdrawal eventually? Cutting up those pills into tiny accurate doses is impossible.
I'd recommend a visit to a G.P/family doctor within the week especially if symptoms don't improve just to check physically you are fine. They may want to prescribe a Benzo or titrate you off the antihistamine. If they offer you antidepressants (with no life events present) ask to see another doctor - unless its Mirtazapine or Trazadone, in which case both are good options. A low dose of an atypical antipsychotic would work to (ex. 25mg quetiapine). They should however run standard bloods (FBC, LFTs, TFTs etc..) and take a history. Also get some water down you, practice some mindfulness and and CBT techniques, whether the cause is physical or psychological they will take some of the edge off.
Yeah, I think I'll see my doctor in the next few days, this is crazy .. I'm just lying around writhing constantly, or always have to be on the move. I was hoping it'd pass on its own because I don't wanna have to start something heavy-duty for the symptoms .. weird that such a tiny dose did this, could it be some kind of 5HT2 rebound sensitivity?