How does alcohol affect SSRIs?

Here’s the Mayo Clinic’s explainiation, which is pretty good: http://www.mayoclinic.org/diseases-conditions/depression/expert-answers/antidepressants-and-alcohol/faq-20058231

In general alcohol is a Central Nervous System (CNS) depressant. This is not the same as the disorder Depression, but what it does is slow down your nervous system, essentially, and in a very general way. Having two different drugs, one targeted and one general, affecting your nervous system is a tricky problem. Two targeted drugs can many times be okay, but even that a doctor needs to look at and check. A general drug like alcohol just tends to wreck havok.

Specific to SSRIs, just looking at a list of potential side effects I can tell you why it may not be a good idea: drowsyness, nausia, headache (from a hangover or before), weight gain, vomitting, and dizziness are all potential side effects shared between alcohol and SSRIs. Taking both drugs has a chance to severely increase the intensity, or make side effects appear when you weren’t experiencing them before. For instance, my gf used to not get hangovers, now that she’s on SSRIs if she drinks one or two drinks even, she gets really bad ones. Your milage can and almost certainly will vary, but the risks are there.

Now, if you want the real scientific mechanisms behind all of this it’ll take more digging, but I can look if you’re interested.

Interesting, in a brief search on the science I’ve found that Venlafaxine and Alcohol both work on norepinephrine, a neurotransmitter (Venlafaxine is actually not a strict SSRI, but an SNRI, or ‘Seratonine-norepinephrine reuptake inhibitor’).

In short, in one of it’s activities, alcohol stimulates GABAa in your cerebellum, which interacts with norepinephrine receptors to make you drowsy. Venlafaxine makes it so that there’s more norepinephrine around (that’s what ‘reuptake inhibitor’ means, they stick around in the synapse longer). So you have drowsiness signals coming from two places at once, not a great thing. It could make you sleepy really fast, could make you sleep for way longer than you’d like after taking alcohol, could make waking up really hard, etc etc.

And, alcohol also interacts with some norepinephrine receptors directly, and those receptors are found all around your brain, so again having two meds working on the same receptor can lead to lots of different effects. Since Venlafaxine stimulates them indirectly and alcohol usually depresses signals, I’d say usually you’re looking at a cancelling effect, though really alcohol’s effects are pretty random so you’ll most like also get some strengthening effects like in the case of drowsiness.

@BhacSsylan That was just what I was looking for when asking this question. Thanks for taking the time to research it too.

Great! Happy to help, it’s an interesting interaction.