Sudden alcohol intolerance

Hi everyone,

I’m writing because I’ve been having a very strange reaction pattern that started after what seemed like a food poisoning about two years ago, and it’s getting more confusing.

Since that episode, I’ve developed a consistent and reproducible reaction to alcohol — and more recently, to cigarettes, but not to any food.

Here’s what happens:

Sometimes while drinking I already feel slightly hot, flushed, or lightheaded. Other times I feel fine in the moment. Regardless, I’ll always sleep terribly that night and wake up extremely nauseous, fatigued, foggy-headed, and off balance the next day. The symptoms last most of the day and then disappear. There’s no abdominal pain, reflux, or heartburn, and I can eat anything without issues.

The alcohol reaction started around October 2023, and since then I’ve essentially stopped drinking. Until recently, I could still smoke occasionally with no problems, but starting this September, even a single cigarette gives me the exact same reaction: disturbed sleep, nausea, fatigue, and brain fog the next day.

So far I’ve done:

H. pylori stool antigen test: negative One month of omeprazole: no effect

Everything else in daily life and diet is normal. It’s just these two substances that now cause an almost identical delayed reaction.

Because alcohol and nicotine affect such different systems, I’m starting to worry there might be an underlying issue, maybe something neurological (vagus nerve?), metabolic, or related to how my body processes certain substances after that initial stomach infection two years ago.

Has anyone heard of or experienced something like this, where both alcohol and cigarettes suddenly trigger identical systemic symptoms, without digestive pain or heartburn?
Could this point to something serious that should be investigated (e.g., autonomic dysfunction, histamine/acetaldehyde metabolism, vagus nerve hypersensitivity, etc.)?

Any insight or similar experience would really help. I’m not looking for “just stop drinking/smoking” advice I already almost completely have. I’m just trying to understand why this is happening now and whether I should get checked for something specific.

Thanks in advance 🙏