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User Reviews for Metronidazole to treat Giardiasis

Also known as: Flagyl, Metro, Flagyl IV, Flagyl 375, Metro IV

Metronidazole has an average rating of 6.0 out of 10 from a total of 32 ratings for the treatment of Giardiasis. 44% of reviewers reported a positive effect, while 22% reported a negative effect.

Metronidazole Rating Summary

6.0/10 average rating

32 ratings from 35 user reviews.

Compare all 12 medications used in the treatment of Giardiasis.

10
13%
9
22%
8
9%
7
0%
6
13%
5
19%
4
3%
3
0%
2
3%
1
19%

Reviews for Metronidazole

Lilly123 June 29, 2020

“Took Flagyl for 7 days because the doctor said I had a parasite in my stomach after taking a stool test. Read the reviews and freaked out about having horrible symptoms. The only symptoms I’ve experienced while taking it was some abdominal pain and change in urine colour. Other than that, It didn’t feel like I was taking a new medication. Pros: I felt better after the medication. So I noticed that I have less trapped gas, bloating, stomach noises when laying down. Cons: Remembering to take 3 pills a day with meals. So taking the pill every 8 hours. It’s important to take probiotics everyday! Some doctors fail to mention that. AND to take the medicine after EATING FOOD. DON'T TAKE IT ON AN EMPTY STOMACH- doctor told me this.”

9 / 10
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Anonymous NY · Taken for less than 1 month September 15, 2013

Flagyl (metronidazole): “I took Flagyl and Cipro for giardia and salmonella diagnosis. Both taken for one week. The Flagyl has a terrible taste and you have to drink something besides water while you are taking it because everything tastes metallic. It works to eradicate the infection but I was very happy when the seven days of treatment was over. I also experienced lack of appetite however you must eat something when you take Flagyl or it will upset your stomach. Other side effects experienced: bloating, burping, hiccups, terrible taste in my mouth all the time, lack of energy. But the need for the medication outweighs the side effects and it took care of the infection.”

9 / 10
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parkersean75yahoo.com September 18, 2017

“I've had this for 4 years. I've seen many doctors and have lived very miserably and confused. My mother ignored me and kept calling me a hypochondriac but I wanted answers. Last week they figured it out. I'm on 500mg Metronidazole 2x daily for 7 days. Today is the 7th day. I have never in my life been so terrified of being unhealthy forever. I want to heal. On Tuesday, they will be testing my stool to see if I have rid myself of this infection. If I do not get rid of this stupid bug, I will be soo disappointed. And the metronidazole feels highly toxic. My tongue is yellow from all of the yeast in my body from my gut flora being annihilated. Someone comfort me. ”

9 / 10
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Caius · Taken for less than 1 month June 11, 2015

Flagyl (metronidazole): “After many weeks of diarrhea, no appetite, crappy stomach feelings I went to the doctor to see if I might have Giardia, turns out from stool tests I have something called Blastocystis homini. Well Flagyl is also prescribed for this as well as Giardia...so I'm taking 500mg / 3 times a day for 10 days. I luckily haven't had to take any medicine for years and I have to say, this stuff reaally sucks. If you are feeling crappy while on this you are not the only one. I'm now on the 7th day and really looking forward to being done. Feeling like I can't function / think straight / general listlessness and anxiety like others say is my experience. Doesn't help that I'm generally paranoid about drugs...symptoms of the bug don't seem to be improving.”

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MadrigalsMom August 28, 2017

“I was on 250 mg 3X a day for one week to treat a giardia infection I have likely had for years without detection. My doctor will also have me on a three-day course in about two weeks, in keeping with the cyst cycles. I just finished the course and had no adverse side effects. I took them in the middle of fairly-sized meals and made sure to drink at least a gallon of water a day, along with eating a clean diet. Perhaps it was the lower dose or one of those measures, but I did not even feel fatigued during the course of my medication. Know that not everyone has terrible (or any) side effects. I delayed taking these after reading so many accounts of awful experiences, but I imagine there are plenty of others that have no side effects.”

9 / 10
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Blu July 12, 2018

“I'm taking 5 400mg Flagyl tablets daily with a meal and I feel worse now than I did with Giardia. I've lost my appetite entirely, I've been stuck in bed for a week and now off work. I had been going to work with the Giardia because I thought it was IBS. But since I have been taking this poison (and it does feel exactly like I'm being poisoned), I barely get out of bed I am so fatigued. I am finding it hard to concentrate, my mouth tastes like I have been chewing on aluminum foil. I feel nauseous constantly, constipated and no matter how much water I drink I feel dehydrated. My urine is a dark colour with a strange smell. I have read this drug is an antagonist of vitamin B1 so I will start taking B1 and Magnesium supplements to hopefully improve these horrible side effects. Good luck to anyone reading this. The only reason I have given it a GENEROUS two stars because so far it has worked to reduce my giardia symptoms but once I finish this course, I will NEVER touch this stuff again.”

2 / 10
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Al · Taken for less than 1 month September 25, 2020

“Caught Giardia traveling. Had severe stomach cramps and raging diarrhea for 5 days. Flagyl quickly cured my symptoms. Took 500mg (I weigh 110lbs) 2 times daily. Would recommend this drug. Only side effect was a metallic taste on day 4. Took meds with food.”

10 / 10
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Frequently asked questions

Feel like death · Taken for less than 1 month April 22, 2016

“I have no idea whether my symptoms are from the giardiasis or flagyl. I have constant headache, abdominal pain, nausea, can't eat, major weight loss, and severe fatigue. I cannot work and am barely functioning. Whatever is causing this, I hope it goes away when I am done with this drug. I have never been so sick in my life.”

5 / 10
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Anonymous August 16, 2009

“During my 7 days on this medicine I experienced a very bad metal taste in my mouth. I was also constipated and had headaches. The medicine cleared up the Giardia and all the symptoms stopped about a day or two after my last dose.”

6 / 10
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Squeakywheel · Taken for less than 1 month September 20, 2021

“Been suffering with severe diarrhoea fir 7 years off and on. Dr said irritable bowel. Live super clean great diet . Stool samples done nothing remarkable . Though I do believe it depends on the laboratory. Flagyl is my only relief . I want to take it for ever. No serious side effects . I had a gastroscope and biopsies taken, 4 days later felt like I was dying . Living on the toilet and a fever . Had to just about get on my knees for dr to give me Flagyl . It was magic so I’m trying to find out if I can take it permanently.”

10 / 10
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Evejude · Taken for less than 1 month June 25, 2015

“On day 7 of 10 of taking Metronidazole and i still feel like shit! Being treated for a parasite that was making me feel awful but not this awful! I know in the long run this will be beneficial as the parasite will be gone however, taking for ten days is exhausting. I have had to take the entire week off work. Side effects include stomach pain, nausea upon movement, brown urine, back pain, fatigue. And the foul taste!!!! People really haven't exaggerated the taste - it is vile and constant! Can't wait to be done!”

5 / 10
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Steve · Taken for less than 1 month December 5, 2018

Flagyl (metronidazole): “After 2 weeks of severe diarrhea just surviving on electrolyte drinks doctors were suggesting surgery. Flagyl was suggested by an experienced traveller a total of two 400mg tablets taken 4 hours apart completely cleared it up. That was 25 years ago. Since found it useful for acid reflux. It is a strong drug so still use after other options have been excluded.”

10 / 10
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Super Sayan · Taken for less than 1 month July 24, 2020

“Caught giardia from our new kitten that was spreading her feces everywhere. Vet lab confirmed she had it, so my case is so far presumptive. Socialized health care in Canada means I won't get the actual results of my stool sample for up to 5 days. I'm on day 4 of 7 of metronidazole(500 mg x2 / day) of metronidazole and feeling a little better I suppose... definitely got worse before getting better. Still, I'm having mental fog, no energy and tired, headaches, very nauseous, and depressed. Still having diarrhea, but it's not explosive like when my symptoms started. It's an awful drug. I really hope it's working.”

4 / 10
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Anonymous August 14, 2011

“I was on 250mg 3x a day for 10 days. It cured my Giardia, but made me very nauseous. My doctor had to give me antinausea medication (Zofran), just so I could keep the pill down. I also experienced a bad metal taste in my mouth for the duration of the treatment.”

5 / 10
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Mtlguy · Taken for less than 1 month August 27, 2017

“Was prescribed 500mg three times a day for 7 days for parasite. On the 7th day I started feeling better and my stools were returning to normal. For 3 days after the end of treatment I felt soooo good, I thought I was cured... only to be sick again on day 4 after treatment. Maybe I need a longer treatment or another antibiotic. However I saw a difference after taking it. In my case the side effect were awful tast in the mouth and dark urine, but nothing is comparable to the symptoms of this evil parasite that I am dealing with since 2 years thinking I had IBS ...”

6 / 10
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Lizzie · Taken for less than 1 month September 4, 2018

“I am in the middle of a 5 day, 3x250 mg treatment for giardiasis. I don't know yet if I have got rid of the bugs for good, but metronidazole has been a life saver for me so far as my stomach cramps used to keep me awake at night. I also want to thank my doctor for listening to me and having me tested for parasites even though she did not think that it would be useful! I did have a headache on the first day, and I still feel the metallic taste in my mouth, but I will take that any day compared to what I was going through before taking the medication (I am taking a relatively low dosage though which may explain why the side effects are mild).”

9 / 10
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2NeverAgain2 March 5, 2016

“I had an intestinal parasite after a trip to Central America. I had a very difficult time in this drug. I'm a healthy, 40 year old woman and the side effects put out for the 5 days I was only this pill. I was taking 750mg every 8 hours for 10 days. I called my doctor and had to stop after 5 days. Severe headaches, nausea, weak, fatigue. I couldn't work and had to rest all day. Metallic taste as well. I would not take this drug again- I would ask for another treatment. It's an aggressive drug that was difficult to tolerate.”

8 / 10
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Russell · Taken for less than 1 month May 20, 2019

“For me metronidazole is simply does not work for the treatment of Giardia. I was prescribed 400mg x 3 per day for 5 days. The drug also has some nasty side effects, tight achilles heels, mental confusion and I was off balance whilst walking.”

1 / 10
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Dcuppluke1019 May 21, 2016

“I returned from India and started having terrible diarrhea within a few days. It continued for two weeks before I went to the doctor. I lost 14 pounds in two weeks. The doctor also gave me cipro. Within 12 hours my diarrhea stopped and I started to feel better. To me this is a miracle drug. I am not sure how must longer I could have gone without being admitted to the hospital.”

9 / 10
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Jackis · Taken for less than 1 month July 27, 2016

“I've been experiencing intermittent diarrhea for like 4 weeks, unsure y. Doc prescribed me dis med. (Dazomet) brand. Today's my last day. These are d things i'm experiencing since day 1: 3xday 500mg for 7 days. 1) dark urine almost brown (the smell of antibiotic makes me vomit) 2) bloated and stomach cramps 3) abdominal pain 4) I also feel like i have a flu 5) behavioral changes (i've been depressed, clingy etc..) 6) I cant sleep that much due to mentioned cramps and i feel tired and weak. 7) loss of appetite. I don't want to eat much even if i want to, because i feel like vomitting everyday. But i feel a lot better now. The side effects are lesser and tolerable as day goes by. Diarrhea did not come back and will go back to doc for follow up”

6 / 10
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Cfowler · Taken for less than 1 month January 31, 2021

“I am a 19 year old female. I began taking this drug because I had a parasite that was causing me terrible symptoms. When I started metronidazole, the first 2 days I slept for a total of 36 of 48 hours. Then every morning I began feeling so nauseous and vomit. This happened like clockwork every morning at around 5:45am. It made me not feel like myself anymore. I couldn't finish the last 2 doses because of the severity of the side effects. And even worse, to top it all off, it did not get rid of my parasite. So now I am trying new antibiotics, hoping they won't make me as sick. Metronidazole is the WORST medication I have ever taken, if there is another option for you, take it.”

1 / 10
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AQ1969 May 26, 2013

“Had recurring giardiasis. Not serious this time because I knew what it was and didn't let it get past the first week of symptoms. I'm taking a very low dose so my symptoms aren't bad. Just avoid dairy for half the time between doses. I'm also using Stevia instead of sugar. I have an 8 hour race on my last day of taking this, so fatigue isn't an issue.”

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Tintan123456789012 September 28, 2015

“Female, 120 lbs. Was prescribed this medication for a parasitic infection (blastocystis) at 500 mg three times a day for 10 days. I had the pharmacist turn it into 250mg twice, 3 times a day as I have trouble swallowing large pills. After the first day of taking these I woke up at 2 am and vomited a total of 6 times before the gravol finally kicked in. Been taking gravol along with my meds ever since. Also been experiencing brain fog (possibly due to gravol), severe fatigue (gravol again?) and loss of appetite. You absolutely must eat food before taking these, especially if you are prone to nausea like me. Won't know if the med even works until I do a stool test after the 10 days.”

5 / 10
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Slippers · Taken for less than 1 month March 2, 2020

“Hi I am so mad, the hospital sent me home, told me they didn't do a stool sample, the follow up called. They did the test, blood, crypto and Guardia. This is the second time, same hospital. Looks like I am going back to get the right treatment. I'm sick and tired of being sick!! Thanks Dr”

1 / 10
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G-boss May 4, 2017

“I'm 4 days into a 7 day treatment for suspected giardia - 400mg 3 x per day. 46 yrs old. No previous giardia or metronidazole. Giardia symptoms started improving within 48hrs. Nausea gone. Stomach pain gone. Diarrhea gone. Low fever gone. But these pills really knock me down. About 40 mins to an hour after taking the pill, I get tired, jaded, thick headed for 2-3 hours. Anxiety too. I'm really looking forward to finishing the course. And I really hope they work!”

5 / 10
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This information is not intended to endorse any particular medication. While these reviews may be helpful, they are not a substitute for the expertise, knowledge and judgement of healthcare professionals.

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