How much time to give mirtazapine?

[panic_down_under]

I have scared myself that it won't work by spending too much time googling...

Googling is counterproductive. Especially when you don't understand what you're reading.

I am worrying that the Fluoxetine will be too stimulating and therefore will make me more anxious rather than less. As I read somewhere that Fluoxetine increased noradrenalin in rats in a study...

Are you referring to Bymaster FP, 2002? If so, yes, they found fluoxetine increased noradrenaline, aka norepinephrine in the extracellular fluid, not within the cells. Also, the study only examined what happens with acute administration, i.e. a single dose. It also found, as you'd expect, that there was an increase in serotonin, aka 5-HT. That happens with all SSRIs and other serotonergic ADs and is the cause of many of the initial side-effects. But with chronic dosing serotonin levels drop back to well below pretreatment levels. See, for example Caccia S, 1992. Because of the long fluoxetine half-life brain serotonin levels take weeks to rebound to pretreatment levels after the med is discontinued (Trouvin JH, 1993)

I haven't been able to find a study which tested noradrenaline levels after chronic fluoxetine administration, but I'd be surprised if they also didn't drop significantly after a few weeks. This is what happens with noradrenaline reuptake inhibitors such as desipramine, (Zangen A, 1999).

And I am worried that the reason that Mirtazapine didn't work as it was increasing my noradrenaline.

How do you know that mirtazapine was raising your brain noradrenaline levels? Stress itself greatly increases it too and also brain serotonin levels. It is one of the proofs that anxiety disorders and depression are not caused by insufficient brain serotonin, or noradrenaline.

I know I shouldn't google but it seems like a compulsion...

You're not helping yourself by doing so. Just the opposite it seems.

I am worrying that the fluoxetine will give me insomnia as I do tend toward insomnia and feel I have only been sleeping recently because of the mirtazapine .

It may do, but how does crossing bridges before you get to them help? If it happens then it can be treated. Small doses of mirtazapine being one of the remedies.

[spiral]

Thanks for all of these points.
Basically all of what I said was stuff I "learnt" on Reddit. I'm assuming that that is the study but I've forgotten the names. I only read the abstract as you needed a login so I accepted the interpretations on Reddit.
I need to stay off Reddit it's even worse than Google.

I think crossing bridges before I get to them is how I've got myself into this state in the first place.

[spiral]

I don't know how to quote your post but in response to "How do you know that mirtazapine was raising your brain noradrenaline levels?"

It was NHS website that sparked it all of as it says this about mirtazapine:
It works by increasing the activity of mood-enhancing chemicals called noradrenaline and serotonin in your brain.

In any case however it works I need to follow your advice and stop googling as I don't have the time or inclination to read everything in enough detail to understand it properly.
I just need to be patient and see if fluoxetine works and if not try something else.
Patience isn't my strong suit...

[panic_down_under]

I need to stay off Reddit it's even worse than Google.

Indeed.

It was NHS website that sparked it all of as it says this about mirtazapine:
It works by increasing the activity of mood-enhancing chemicals called noradrenaline and serotonin in your brain.

The website is wrong. The 'chemical imbalance' hypothesis as being the cause of anxiety disorders and depression was dismissed almost as soon as it was proposed, but it has become a zombie myth which refuses to die in large part because it's a simpler concept for doctors and pharmaceutical companies to 'sell' to patients than the real cause. My 'Serotonin - The 'chemical imbalance myth' post explains why it's doesn't stack up.

[spiral]

Great post, thanks.