Is this a side effect of the medication?

[SweetDreamsNeeded]

I’ve been taking Sertraline for a few years now but recently I’ve had a few side effects, ie. spiders, my mind starts thinking of them. I can be in the shower or sat reading in bed when they come into my head. Slugs are another one, leaving me feeling sick. Why can this be happening now? Has anyone gone through similar?

Hi OP,
I can only speak for myself but I’ve never experienced such thoughts (& I’ve been on sertraline for a couple of decades). However, I have hallucinated smells - specifically, perfectly cooked jacket potatoes! No other smell, and in a variety of circumstances inside & outside.
Whether that aligns with your creepy crawlies I don’t know, but if it does then you’ll be pleased to know that the aroma passed after a few weeks.
Best wishes for the reduction in the symptoms for which you’re taking the meds, I’ve found it to be life changing; it’s definitely worth persevering.

That sounds like OCD/intrusive thoughts. I’ve been on a high dose of Sertraline for about ten years now, and that’s not something I experienced, personally, as a side effect.
However, I have checked, and intrusive thoughts can be a short term side effect to Sertraline. If you have been okay, until now(you mention taking Sertraline for a couple years?), and this is a new thing, then you need to see your doctor.
There could be many reasons, like, if you have recently upped your dose, then often your original issues (the reason why you are on it in the first place), tend to temporarily increase. I remember my anxiety was almost unbearable for two weeks, after they increased my 100mg to 150mg.
Or, stress can cause intrusive thoughts?
Try not to worry, there’s lots of things they can do to help.