man screaming in pain or anger

Americans think of antibiotics as silver bullets. Our reverence for this type of medication is understandable. Before penicillin was developed, people routinely died from pneumonia and other infections. With this miracle of modern medicine, such deaths have become rare.

Because antibiotics are perceived as wonder drugs, physician and patients tend to overlook their side effects. A little stomach upset or diarrhea seems like a small price to pay for curing a nasty infection.

Quinolone Antibiotics

Sometimes, however, the side effects of certain antibiotics are unexpected and severe. One class in particular, fluoroquinolones, can cause unanticipated trouble. The most frequently prescribed are ciprofloxacin (Cipro), levofloxacin (Levaquin) and moxifloxacin (Avelox).


Readers of this column have shared some frightening experiences. One wrote:

“My husband took Levaquin for a sinus infection and within hours the tendons in his legs tightened and he could not walk. It took months for him to get better though he still has some residual leg pain.”


Another reported:

“Some ten years ago I was prescribed ofloxacin (Floxin) for a sinus infection. The next evening I woke up from sleep and began hallucinating that HUGE bats were flying around the room.

“The experience absolutely terrified me. I thought I was losing my mind. My sister, who was a pharmacy representative, had warned me not to take this antibiotic. I dismissed her warning as empirical hogwash. Needless to say, I had to learn the hard way.”


A parent described her daughter’s reaction:

“My 27-year-old daughter has spina bifida. I told the urologist treating her for an infection that she could not take Cipro because it had caused seizures. He said he wasn’t aware of that problem and that Levaquin was a chemical cousin and shouldn’t cause the same problem.

“On day four of the medication she had a seizure. That makes four times she’s had seizures on a quinolone, and it still took us the parents to make the connection. The doctors aren’t aware of this effect.”

Brain Fog

A 19-year-old sent his report:

“I am a college student who is still suffering the effects of Levaquin months later. My doctor prescribed it for painful urination with a fever. Within an hour of taking the first dose, my legs felt numb and it seemed like my brain was frying. I couldn’t explain to my mom what was happening and I could barely move. It wasn’t that I was paralyzed; more like I was walking on a water bed. I had no balance, my gait was terrible, and I couldn’t think.

“My doctor thought the neurological symptoms I was experiencing were due to fever and dehydration, but really it was a consequence of the Levaquin. I still have deep pains in my knees and feet and I am too weak to exercise as I used to. But the biggest problem that bothers me is the brain fog. I get lost easily, cannot remember things and had to withdraw from school. I am wired-tired and have great trouble sleeping.”

These quinolone antibiotics can help clear infections. They can also cause distressing side effects such as tendonitis, tendon rupture, insomnia, dizziness, confusion, hallucinations, psychosis, movement disorders and seizures. Even silver bullets can cause serious damage.

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  1. Salim

    I got middle & external ear infectons ..
    The doctor described 2 g amoxillin & 750 cipro

    I read alot of side effects .. I have a black dirrhea ..

    It’s my third day.
    I am just afraid what will happen after I finish my course ..

  2. Rajani

    I have been having UT I since almost a year. I took norfloxacin for 5 days last year. After 15 days, I suddenly had fasciculations all over my body including face. Then pins and needles, cold flashes, eye problems, many more neurological issues. Brain fog was so horrible that I couldn’t even order a cup of coffee from the shop. It spoiled my personal life and career. All my MRI, EEG, EMG, blood work came out normal.
    Can anyone tell me natural ways to reverse these side effects?

  3. MJ

    The doctor put me on Cipro for a tear duct infection. I took one pill 7pm before bed and by the next morning I was feeling like crap. I took another pill at 7am and by 10am my right leg was hurting so bad. It also felt like I was walking on needles. I also had pain in my shoulders and neck muscles. About 1:30 pm I had enough and called the doctor who said to go to the walk in clinic. I went and the doctor told me to stop taking the medication. If I got that sick after taking only 2 pills I can just imagine what would have happened if I taken it for the full 7 days.

  4. Andrea B.

    I also thought I was going crazy!!

  5. Andrea B.

    Had cipro for almost month about the third week I was so messed up I thought I was dying it made me feel awful. I had tendon problems in my achelies heel and now in my hands and fingers. I can’t even bend my fingers open and closed they just get stuck(stiff) I know it was the cipro!! I will never take it again

  6. andrew
    Kansas City

    I had antibiotics when I was six weeks old to about 4 years old due to ear infections. I have really bad memory and fogginess all the time. I’m tired of feeling slow, does anybody know anything that can help my brain function better? thanks!

  7. Dawn

    I’ve suffered many bacteria infections and when I take antibiotics, I can feel it my brain, hard to explain. But some things not right with this. I’ve never heard of anything affecting and as I would describe movement in my head?

  8. KJ

    I have just experienced a severe allergic reaction to ancif IV after minor surgery. I feel terrible with upper arm muscle cramps, severe weakness et. This is very frightening as I need to return to work next week.. I am trying to understand if I have fluoroquinoline poisoning.. thanks for these posts as I attempt to try to figure out what has happened to me. My doctor advised me that these symptoms will only last for 14 days, its now day 13 and I still feel awful.. Any advice would be appreciated!
    I have been doing a liver cleanse for two days now, Dr. Oz ..

  9. SDN

    Hi all, 1st off I’m sorry to hear about the complications that so many are experiencing. I realize some of these comments go way back but it is obvious that this thread is active and since I read every single comment I wanted to add mine. At this moment I’m on Cipro and Flagyl for what may be a parasite infection likely caused from recent previous antibiotic intake. I took Keflex about 3 months ago and then recently Cipro for 14 days for staph. I was admitted for 1 1/2 days in isolation on both antibiotics (Cipro/Flagyl) IV. Then sent home and have about 3 days more to take of both of them. Before being admitted, the admitting Dr. who was called in talked to me. He said there are 2 main causes for what they believe I have (waiting on a test to come back) 1) hospital stays of any length and I was in the hospital just for observation for 1 day about 2 months ago. 2) antibiotics kill good bacteria and sometimes we can get C. diff. (bacteria)
    All my life I have had issues with antibiotics mostly stomach upset and often headaches and then dehydration which lead me to ER and sometimes another antibiotic to correct what the former antibiotic caused. Are you getting the picture of the vicious cycle that antibiotics can cause? HOWEVER, in some cases antibiotics are life saving. I also didn’t know then what I have learned now.
    I do want to share that Augmentin for me by far caused me the worst experience of all of them with regard to severe joint pain. I stay away from that one. What I have learned is that I can take antibiotics now as long as I take Protonix. I take it in between doses. It has made a huge difference but get a good Protonix if you choose to go this route (good doesn’t mean expensive). Eating yogurt just isn’t strong enough for me. What my Doctors have taught me is when I am given an antibiotic and if I have any strong reaction like numbness, swelling, severe diarrhea, etc. after dosage, then it could be an allergic reaction. It is wise to call your Dr. right away or go to ER and get treated. Some of the comments above seem to indicate allergy to the antibiotic.
    What I feel I did wrong this time with back to back antibiotics and a hospital stay that has made me so very sick is that I was weak after 2 rounds of antibiotics and slept so much that I was missing my doses of vitamins and supplements and not eating much and not eating right either. I have a couple medical conditions that added to the fatigue and I have to take my vitamins and supps for my immune system.
    A comment was made above that was right on about taking the vitamins listed, drinking hot water with lemon to detox liver etc., green tea is a good thing to drink as well and this can help after antibiotic treatment. We as patients have to be totally involved in our care and research. Doctors hate that, well it’s our life. I will never make that error again and will take the good things to help my body recover after antibiotic treatment and especially not miss the Protonix (or Prebiotics) which helps with the good bacteria we all need.
    But I can say honestly that when I have a condition that I agree with the Dr. that I need an antibiotic, I will take it. You can’t let a staph infection or other serious illnesses go and not get help. I didn’t read any comments that explained that at times we have to have antibiotics. In life in general eating good food, grass fed meat, lean towards organic foods and taking your multi and supplements can help greatly to reduce the frequency of needing antibiotics. Prior to this recent experience I went a couple of years without any antibiotics at all. Sometimes we just get sick enough that we need medicine. I also don’t jump right away to get antibiotics and try for a couple days to take extra vitamin C, get more rest, etc to see if I can get better.
    I also agree very much that Doctors should discuss the potential side effects and reinforce the main symptoms to watch for which can indicate an allergy to that antibiotic and to get urgent care right away. The pharmacists are a great resource as well.
    I hope everyone has recovered well by now. I know some have suffered a lot and it’s so sad. I also hope that when you all do need help with a condition that you get it and keep track of what you all can and can’t take. Write it down and have it handy at all times in case of emergency.

  10. N,D.G

    I have not read the comments but the “article” itself is purely anecdotal. There doesn’t appear to be any proven facts to back up the claims. Anyone can just say something and who would lie on the internet? RIGHT?

  11. SB

    I was prescribed 875mg Augmentin for what my doctor thought was a sinus infection. Half way through the 10 day treatment my body felt achy all over, was weak and I ended up suffering stroke like symptoms – facial numbness, tingling in my left arm and my head ached and was in a fog. I ended up in the ER on two separate occasions. They performed a CT scan and MRI and found nothing. I hope that the lingering symptoms will resolve with time. This makes me very leery about taking this and any other medication in the future.

    • Martin

      Mind you I have been taking cipro and I have never dealt so bad in my life. I have stopped smoking weed and due to the meds I have been suffering from a swollen throat, anxiety, heart palpitations symptoms of IBS, sticky black stools with mucus, but yet the doctors say nothing about it they just tell me to finish my meds but they don’t understand how I feel or it seems like they don’t listen, my doc said I would have an upset tummy but didn’t tell me all of what could happen. It’s disgraceful if anything happens to me I will be sure to sue them.

      • Angie

        You might have cdif. go to hospital tell them to check you out ASAP I know the signs I’ve been there. I got cdif from being on some many antibiotics not just one time but a few times now my legs are numb and week and I have to now have my Colin removed. It’s not fun-I’m in pain all the time.

    • MG

      SB – did your symptoms ever go away? I have been having similar symptoms.

    • johnnie

      i took augmentin my dr. prescribed even after the pharmacist said she should not give it to me because of liver disease and hep-c post op transplant patient. The doctor did not listen and gave it to me.

      I took 1 or 2 pills and ran back to my dr. as fast as i could go with side pain in my liver and a severe rash on my chest and throat swelling. She checked me out and sent me home and said your ok.

      I didnt believe her so i went to get labs done /blood work and the next thing i knew about 45 minutes later i was called into the specialty clinic at va hospital gi clinic and was told by the dr you are ”liver failure” dying. I cant believe my dr. didnt listen to the pharmacist who told her not to give it to me because of my past medical history of liver transplant /hep-c

  12. LL

    Hi all, last year around the Christmas holiday I took levaquin for a sinus infection. Well three days into the five day treatment my shoulders hurt a bit, but by day five I could barely raise my arms to lift my newborn! Fast forward to this past September my knee just came undone! (dislocated my right patella and tore tendon) I wasn’t running or jumping or turning sharply! All I did was stand up!!
    Today I’m just now learning to walk without a limp and still can’t bare full weight! What’s even more scary is now it feels like my right elbow is about to come apart too!! Also, at times I lose use of my arms… painful and difficult to raise them up! All this suffering from taking something that’s suppose to be beneficial! I’ve spent two months on crutches and 2 1/2 months in therapy. I recently had pain in my left knee too I’m praying that one holds up!

  13. Kh

    I am 64 and have had almost continual UTIs this past year for which I’ve been on almost continual antibiotics (varying ones but not CIPRO). Now I have frequent thigh pain and calf cramps (mostly in one leg). I’m unable to sleep at night because of the pain (especially when I try to sleep on my sides). It also aches during the day when sitting at work.
    Could the pain be related to too long a period of antibiotics? I take calcium, magnesium, zinc pills every day (previously prescribed for restless leg syndrome).

  14. Joseph O.

    I was diagnosed as having silent reflux causing a lot of sinus drainage as was prescribed Nexium 40 mgs twice daily and Amoxicillan for 28 days did not make a connection at the time or before but aprox 2 weeks in my ankles swelled and stiffened up and so did many joints in my body hands, fingers, knees achille’s tendons, elbows, shoulders, neck. My right knee is on fire if I kneel also extreme weakness, brain fog, gastric problems, dizziness, I can barely walk sometimes my walking is getting better went to Rheumatologist he thinks it could be early signs of RA but did not have these vast problems until the antibiotics some area seem to be getting better. Was on this therapy almost 4 weeks I started in July I believe is right and now almost November still having problems I return to Rheumatologist Nov.9

  15. em

    I only took one pill 875mg augmentin. It made me so sick I never took another one. Now, a month later bad leg aches. Did you ever get better? How are you? I’m afraid its going to be permanent please let me know what you think. All my levels from cbc came back normal so I’m not sure why the leg pain and it won’t go away. Thank you I really pray you are better!

  16. ll

    I have had problems with Cipro and pain ever since. I take name brand Zithromax it’s just one pill a day for a week. I make sure I eat activia yogurt before bed because you shouldn’t eat it near the the same time you take the Zithromax. one thing I think is very important to note is that the generic versions of pills aren’t the same as the name brands. It’s about the fillers and inactive ingredients being different which can cause the active ingredient to be less effective. Generics only have to be 80% as effective, yet it is shoved down our throats that they are the same as the name brands.
    There is a book called the Orange Book that goes into scientific detail on generics versus name brand formulations. Generics don’t dissolve in your stomach the same either.
    I can personally attest that I took generic Zithromax and ended up needing TWO courses of it instead of the one course of name brand Zithromax. name brand Zithromax works in two days for me but the generic didn’t work at all in a week! The bio similars that are coming out are going to be way worse as those only have to have a “similar” effect. it’s about time the insurance companies get out of forcing our doctors to do or prescribe things. The Drs need to start listening to the patients. We know our bodies.

  17. MNC

    I have an ear with a punctured ear drum. Because of that, I get frequent ear infections. I have been been using Ofloxacin Otic for the last five years. For the past 3 years I have been dealing with a chronic insomnia that is driving me insane. Lately, I decided to research the prescribed medication. Side effects mention central nervous system damage. I am convinced this medication is at fault for my insomnia. Is the damage reversible? I would appreciate any comments.

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