Fluoxetine and insomnia

[USER12]

I have been taking fluoxetine for 4 months now, 2 months at 20mg and 2 at 30mg.

I have been experiencing insomnia, can’t stay asleep for more than two hours at night. I take it first thing in the morning.

Should I stick it out or change to a different medication? What can I do to help with insomnia?

[panic_down_under]

I have been experiencing insomnia, can’t stay asleep for more than two hours at night. I take it first thing in the morning.

Insomnia is one of the most common initial side-effects when first taking SSRIs. It usually diminishes after a few weeks, but can be an ongoing problem for some.


Should I stick it out or change to a different medication?

Changing to another SSRI may make a difference, but there are no guarantees. As per above, insomnia is a common side-effect of all SSRIs and some other serotonergic ADs. If you do need to switch anecdotally citalopram (Celexa) is supposedly less likely to cause sleep problems.


What can I do to help with insomnia?

I suggest you talk to your GP about this. You are likely to be offered either a benzodiazepine (BZD), one of the 'Z' class hypnotics, or a sedating antihistamine such as mirtazapine.

I'd avoid BZDs because they inhibit the mechanism by which SSRIs work (Sun Y (https://www.ncbi.nlm.nih.gov/pubmed/23639432), 2013).

Eszopiclone ( Lunesta) is the pick of the 'Z' hypnotics as it may increase the effectiveness of SSRIs a little (Su XW, 2009) (https://doi.org/10.1017%2FS1461145709990629). The others might also, but there isn't enough evidence yet to be sure.

While mirtazapine is classed as an AD, it is really just a very sedating antihistamine and at small doses, <=15mg, can be very effective sleep aid.

Even better would be low doses, <=75mg, of another AD, trazodone (Desyrel). While an effective AD, these days it is mostly only prescribed to treat SSRI induced insomnia. However, it doesn't appear to be prescribed much in the UK so you might have trouble getting it, but it won't hurt to ask. It's advantage over mirtazapine is a shorter elimination half-life - 10-12 hours -v- 20-40 hours - so sedation is less likely to continue into the next day.

[USER12]

Thank you panic_down_under.

I was on escitalopram but switched to fluoxetine, might try going back to it again.

[panic_down_under]

I thought you switched from escitalopram because it wasn't working even at the recommended maximum 20mg/day?

[USER12]

I did, but I’ve been thinking maybe I should have given it more time. Not sure what to do tbh.

[panic_down_under]

How long were you on escitalopram 20mg?

[USER12]

Only two months, although was on lower doses before for around 3 months.

[panic_down_under]

If you were on 10mg escitalopram for at least a month before increasing to 20mg then you should have seen some improvement if it was going to work. Give it another shot if you really want to, but I'd try something else if you can't get the fluoxetine triggered insomnia under control.