r/Antibiotics

I was prescribed doxycycline 100 mg twice a day for a UTI and just finished the course today. My anxiety has gotten significantly worse while taking it, and I'm hoping it's related to the medication and temporary. I had to take it for 7 days yesterday was the last pill and today is a new day but my anxiety and thoughts are still out of control (yes I have a therapist).

Has anyone else experienced this? If so, how long after your last dose did your anxiety start improving?

Currently taking metronidazole. Pharmacist told me you can't drink alcohol while taking it, but is THC safe? Im going to a 4th of July party and knew I couldn't drink so I was thinking THC drinks? I can't find anything online about it. Does anyone have any similar experiences with THC and metronidazole?

Fuck this shit. I finished the 4th day of 500mg 3 days ago, and I am still feeling like shit.

Got it for walking pneumonia and felt much better with the pneumonia on it’s own.

My heart rate is super sensitive, just standing up makes it go to 100 when my normal is 75-80.

Major DPDR.

Not an allergic reaction. These are definitely side effects.

I left my antibiotics in my car. It’s hot and humid where I am. Will they be affected/is this dangerous?

They smell weird when I smell them, but I hadn’t smelled them prior before they were in the hot car.

I have heard good and bad, but trying to narrow it all down with specifics - an e coli UTI and Bactrim and if it did in fact clear the infection and what you did to mitigate any negative reactions. The dose would be short-term 5 days, but anything you can share from your own personal experience would be helpful.

I want to share my experience so that someone who has this issue knows its from the antibiotics & maybe it will help. I had to take an antibiotic for surgery precautionary. I took 500 mg 2x a day for 4 days. At first I had issues falling asleep but i chalked it up to discomfort from my surgery/ anesthesia. Well that lasted 3 days. I could not fall asleep no matter what and I never had that issue before in my life. I wasnt taking anything else besides tylenol by this time. I was having crying spells randomly and the worst headache of my LIFE. It was a throbbing fire pain that was pressure in the back of my head that was a 7/10. Not only that but my whole body was vibrating from the base of my beck into my head and it was visible in my hands. Why? Because cefadroxil revs up your central nervous system. I think if it got any worse I would have went to the ER. I was icing my head crying and tylenol would not touch this headache at all! Alarming. Then not connecting the dots I took another pill late at night. That sent me into over drive & I figured it out shortly after. I became restless and wired within 1 hour. I was rocking back and forth and could not sit in one spot but in my mind I wanted to go to sleep. When I wanted to go to sleep I would lay down and close my eyes drift off then jolt back awake. There was zero sleep in sight. The anxiety depression and panic creeped in. It was a horrible experience while trying to heal from surgery. Im still dealing with the side effects I started a probiotic daily and drinking a lot of liquids to flush my body. When i told the dr that this medication did this to me he said no way and brushed it off. But yes it does it is listed as a side affect so do your research insomnia is a side affect of many antibiotics. Most drs dont know the side effects they just write the script. Its been crazy and im still not great but i hope this helps someone looking for answers.

I recently had a root canal and my endodontist gave me antibiotics clindamycin as I’m allergic to penicillin. Took them for 3 days and ceased them as it’s given me bad gut problems liquid diarrhoea and stomach cramps. I have had a stool test but came back negative. My doctor suggested the antibiotics could have triggered inflammation in my bowels. Has anyone had issues with this antibiotics? If so any advice on what you did to get better ❤️‍🩹

I started taking amoxicillin 2 days ago for a tooth infection. The swelling didn't go down much so yesterday I went to the doctor and they put me on amoxicillin clavulanate. I took my first dosage of it last night and I woke up today with diarrhea. I've had to go 2 times already. The right side of my belly does feel a bit tight.

Is this normal? I do have health anxiety and anything abnormal freaks me out. I hate taking medications. I was supposed to take my 2nd dosage an hour ago but I've been feeling a bit nauseous, even drinking water.

Hey everyone,

I wanted to share my story, in the hopes that it would bring some awareness and help others out there. Apologies for the wall of text.

At the end of May, my wife and I traveled to Central America to celebrate her birthday. We were there for about 10 days, and the first few days were great - seeing the sights, eating great food, shopping, the works. About halfway into the trip, my wife got sick with food poisoning. She kicked it after a couple days, which was good, because very shortly after I got food poisoning myself.

It was a horrible experience. I felt completely drained and couldn't really stomach much food, plus all the electrolytes I drank didn't really seem to do much since I wasn't retaining anything. I stayed in the hotel room for about two days dealing with diarrhea and weakness in general. After those two days, I woke up the following morning feeling extremely weak and pale. Nothing was helping - water, food, electrolytes. We were supposed to go to the airport, but instead we went to the hospital where I got stool test and an IV. That gave me enough energy to survive the 5 hour plane ride back to the states.

The day after I arrived back in the U.S., I was still feeling terrible and went to urgent care. They prescribed me Azithromycin and Tinidazole, and ordered new stool tests. The goal was to clear out the source of any infection quickly, as tests in the U.S. take more time. So I started the Azithromycin (500 mg a day for 3 days) and tinidazole, and at first I was okay, feeling a little bit better even. But the following morning I woke up with a tremor in my right arm, and still wasn't feeling right. I took my second dose anyway, thinking it was electrolyte issues, but later that day I went to the ER since I had developed more neurological side effects, including brain fog, headaches, and the whole front of my face going numb. Thankfully all my tests were okay, but it was clear I had a severe reaction to the Azithromycin.

The following weeks were also hell. While those other side effects I listed above went away, I developed severe anxiety, insomnia, and mood swings. I never had any physical or mental health issues up until this point of my life, and never took any medication either. Dealing with this for the first time, with insomnia, was horrific. I went 4 days without really sleeping at all. I cried multiple times a day from the mood swings and anxiety, thinking I would never get back to normal. My primary care doctor prescribed me Xanax, which didn't help either (I only took one dose - caused really bad body shakes, and I still couldn't sleep, plus the anxiety the next day was the first). I then started on trazadone, which helped a little bit here and there. I took it for about a week, and as soon as my sleep got better I stopped since it was affecting my heart and the groginess I felt the next day was extremely debilitating.

Overall, it's been 4 weeks of absolute hell. The Azithromycin is finally out of my system, but I'm still dealing with anxiety and some issues sleeping, plus trying to get my cardiovascular stamina back up. The worst part about this is that my food poisoning was found to be of a viral origin, so I didn't need to take any of the medication in the first place.

If anyone else out there is suffering from something like this, you're not alone. It's taking time to put myself back together, but its happening. After 4 weeks of this, today I finally was able to leave the house and run some errands for the first time. It will get better, just keep fighting.

I was prescribed doxycycline 40mg for rosacea and took this for 8 days. I started getting the worst headaches of my life, dizziness and extreme nausea. I stopped taking them where I then got the worst headache to the point I went to A&E. Since coming off (been off coming up to 6 days today) I am still experiencing bad headaches, dizziness and my mental health has plummeted massively. I have had low mood, severe anxiety and panic attacks alongside feeling hopeless and no motivation. Is there any advice? How long will these effects last!!!

I have mild Supraventricular Tachycardia which isn't the dangerous kind of electrical heart arrhythmia, but still. I've tolerated Cipro fine.

Anyone else with an electrical arrhythmia taken moxifloxacin? How did it go?

It was suspected I had MRSA in my nose so urgent care gave me bactrim to take for 7 days. This was in December 2025. It’s worth noting as well that I had taken some doxycycline on and off a few months prior for acne but not super consistently. So now it’s June 2026 and I have been having type 5, 6, and 7 Bristol stool types ever since I stopped the bactrim. Throughout my life my stools have consistently been types 2-4, very quick and easy for the most part but now I find myself sitting on the toilet for upwards to 20 minutes in the morning.

Has anyone else had this happen to them before? I’m assuming this change is due to the bactrim?