Flagyl (Metronidazole) - Side Effects and Adverse Reactions

ADVERSE REACTIONS

Two serious adverse reactions reported in patients treated with intravenous metronidazole have been convulsive seizures and peripheral neuropathy, the latter characterized mainly by numbness or paresthesia of an extremity. Since persistent peripheral neuropathy has been reported in some patients receiving prolonged oral administration of metronidazole, patients should be observed carefully if neurologic symptoms occur and a prompt evaluation made of the benefit/risk ratio of the continuation of therapy.

The following reactions have also been reported during treatment with Metronidazole Injection, USP RTU®.

Gastrointestinal: Nausea, vomiting, abdominal discomfort, diarrhea and an unpleasant metallic taste.

Hematopoietic: Reversible neutropenia (leukopenia).

Dermatologic: Erythematous rash and pruritus.

Central Nervous System: Headache, dizziness, syncope, ataxia and confusion.

Local Reactions: Thrombophlebitis after intravenous infusion. This reaction can be minimized or avoided by avoiding prolonged use of indwelling intravenous catheters.

Other: Fever. Instances of a darkened urine have also been reported, and this manifestation has been the subject of a special investigation. Although the pigment which is probably responsible for this phenomenon has not been positively identified, it is almost certainly a metabolite of metronidazole and seems to have no clinical significance.

The following adverse reactions have been reported during treatment with oral metronidazole:

Gastrointestinal: Nausea, sometimes accompanied by headache, anorexia and occasionally vomiting; diarrhea, epigastric distress, abdominal cramping and constipation.

Mouth: A sharp, unpleasant metallic taste is not unusual. Furry tongue, glossitis and stomatitis have occurred; these may be associated with a sudden overgrowth of Candida which may occur during effective therapy.

Hematopoietic: Reversible neutropenia (leukopenia); rarely, reversible thrombocytopenia.

Cardiovascular: Flattening of the T-wave may be seen in electrocardiographic tracings.

Central Nervous System: Convulsive seizures, peripheral neuropathy, dizziness, vertigo, incoordination, ataxia, confusion, irritability, depression, weakness and insomnia.

Hypersensitivity: Urticaria, erythematous rash, flushing, nasal congestion, dryness of the mouth (or vagina or vulva) and fever.

Renal: Dysuria, cystitis, polyuria, incontinence, a sense of pelvic pressure and darkened urine.

Other: Proliferation of Candida in the vagina, dyspareunia, decrease of libido, proctitis and fleeting joint pains sometimes resembling “serum sickness.” If patients receiving metronidazole drink alcoholic beverages, they may experience abdominal distress, nausea, vomiting, flushing or headache. A modification of the taste of alcoholic beverages has also been reported. Rare cases of pancreatitis, which abated on withdrawal of the drug, have been reported.

Crohn's disease patients are known to have an increased incidence of gastrointestinal and certain extraintestinal cancers. There have been some reports in the medical literature of breast and colon cancer in Crohn's disease patients who have been treated with metronidazole at high doses for extended periods of time. A cause and effect relationship has not been established. Crohn's disease is not an approved indication for Metronidazole Injection, USP RTU®.

REPORTS OF SIDE EFFECTS / ADVERSE REACTIONS RELATED TO FLAGYL

Possible Flagyl side effects / adverse reactions in 47 year old male

Reported by a consumer/non-health professional from France on 2007-01-04

Patient: 47 year old male

Reactions: Hypersensitivity, Headache, Pyrexia, Dermatitis Exfoliative

Adverse event resulted in: hospitalization

Suspect drug(s):
Clamoxyl
    Indication: Dental Disorder Prophylaxis

Flagyl
    Administration route: Oral
    Indication: Dental Disorder Prophylaxis

Possible Flagyl side effects / adverse reactions in 53 year old male

Reported by a physician from Japan on 2007-01-08

Patient: 53 year old male

Reactions: Diarrhoea, Anaemia, PUS in Stool, Rectal Cancer, Perirectal Abscess, Convulsion

Adverse event resulted in: hospitalization

Suspect drug(s):
Lexiva
    Dosage: 700mg twice per day
    Administration route: Oral
    Indication: Acquired Immunodeficiency Syndrome
    Start date: 2006-01-18
    End date: 2006-01-27

Flagyl
    Dosage: 250mg four times per day
    Administration route: Oral
    Indication: Perirectal Abscess
    Start date: 2005-10-19
    End date: 2005-12-27

Norvir
    Dosage: 200mg per day
    Administration route: Oral
    Indication: Acquired Immunodeficiency Syndrome
    Start date: 2006-01-18
    End date: 2006-01-27

Combivir
    Dosage: 2tab per day
    Administration route: Oral
    Indication: Acquired Immunodeficiency Syndrome
    Start date: 2002-05-03

Other drugs received by patient: Stocrin; Reyataz; Gaster; Takepron; Amaryl; Melbin; Cefmetazon; Voltaren; Calonal; Diflucan

Possible Flagyl side effects / adverse reactions in 12 year old female

Reported by a consumer/non-health professional from United Kingdom on 2007-01-08

Patient: 12 year old female

Reactions: Alanine Aminotransferase Increased, Oedema, Rash, Neutropenia, Pyrexia, Erythema, Thrombocytopenia

Suspect drug(s):
Augmentin '125'
    Indication: Drug USE FOR Unknown Indication
    Start date: 2005-12-01
    End date: 2005-12-03

Cefotaxime
    Indication: Empyema
    Start date: 2005-12-03
    End date: 2005-12-18

Flagyl
    Start date: 2005-12-03
    End date: 2005-12-18

Flucloxacillin
    Start date: 2005-12-03
    End date: 2005-12-18

Meropenem
    Indication: Empyema
    Start date: 2005-12-18
    End date: 2005-12-22

Augmentin '125'
    Indication: Drug USE FOR Unknown Indication
    Start date: 2005-12-01
    End date: 2005-12-03

Cefotaxime Sodium
    Indication: Empyema
    Start date: 2005-12-03
    End date: 2005-12-18

Flagyl
    Start date: 2005-12-03
    End date: 2005-12-18

Flucloxacillin
    Start date: 2005-12-03
    End date: 2005-12-18

Meropenem
    Indication: Empyema
    Start date: 2005-12-18
    End date: 2005-12-22

Other drugs received by patient: Fluticasone Propionate; Acetaminophen; Piriton; Fluticasone Propionate; Acetaminophen; Piriton

Possible Flagyl side effects / adverse reactions in 46 year old male

Reported by a individual with unspecified qualification on 2007-01-16

Patient: 46 year old male weighing 44.0 kg (96.8 pounds)

Reactions: Hyponatraemia, Hypokalaemia

Adverse event resulted in: hospitalization

Suspect drug(s):
Flagyl
    Indication: Lymphangitis
    Start date: 2006-03-24

Claforan
    Indication: Lymphangitis
    Start date: 2006-03-24

Cymevan /00784201/
    Indication: Cytomegalovirus Infection
    Start date: 2006-03-30
    End date: 2006-04-20

Pentasa
    Administration route: Oral

Kabiven
    Start date: 2006-03-13
    End date: 2006-04-20

Solu-Medrol
    Start date: 2006-03-09

Possible Flagyl side effects / adverse reactions in 53 year old male

Reported by a individual with unspecified qualification on 2007-01-16

Patient: 53 year old male

Reactions: Metabolic Acidosis, Coagulopathy, Cholestasis, Pyrexia, Hepatitis Cholestatic, Renal Failure, Sepsis, Circulatory Collapse, Leukocytosis

Adverse event resulted in: death, life threatening event

Suspect drug(s):
Flagyl
    Administration route: Oral
    Start date: 2006-11-07
    End date: 2006-12-01

Moxifloxacin Hydrochloride
    Administration route: Oral
    Start date: 2006-11-07
    End date: 2006-12-01

Vfend
    Administration route: Oral
    Start date: 2006-11-13
    End date: 2006-12-01

Possible Flagyl side effects / adverse reactions in 12 year old female

Reported by a health professional (non-physician/pharmacist) from United Kingdom on 2007-01-18

Patient: 12 year old female

Reactions: Alanine Aminotransferase Increased, Oedema, Rash, Neutropenia, Pyrexia, Erythema, Thrombocytopenia

Suspect drug(s):
Meropenem
    Indication: Empyema
    Start date: 2005-12-18
    End date: 2005-12-22

Augmentin '125'
    Start date: 2005-12-01
    End date: 2005-12-03

Cefotaxime
    Indication: Empyema
    Start date: 2005-12-03
    End date: 2005-12-18

Flagyl
    Start date: 2005-12-03
    End date: 2005-12-18

Flucloxacillin
    Start date: 2005-12-03
    End date: 2005-12-18

Meropenem
    Indication: Empyema
    Start date: 2005-12-18
    End date: 2005-12-22

Augmentin '125'
    Start date: 2005-12-01
    End date: 2005-12-03

Cefotaxime Sodium
    Indication: Empyema
    Start date: 2005-12-03
    End date: 2005-12-18

Flagyl
    Start date: 2005-12-03
    End date: 2005-12-18

Flucloxacillin
    Start date: 2005-12-03
    End date: 2005-12-18

Other drugs received by patient: Fluticasone Propionate; Paracetamol; Piriton; Fluticasone Propionate; Paracetamol; Piriton

Possible Flagyl side effects / adverse reactions in 68 year old male

Reported by a physician from France on 2007-01-22

Patient: 68 year old male weighing 80.0 kg (176.0 pounds)

Reactions: Convulsion

Adverse event resulted in: hospitalization

Suspect drug(s):
Flagyl
    Administration route: Oral
    Start date: 2006-07-01

Flagyl
    Administration route: Oral
    Start date: 2006-10-06
    End date: 2006-10-13

Other drugs received by patient: Tahor; Bisoprolol Fumarate; Kardegic /00002703/; Ramipril

Possible Flagyl side effects / adverse reactions in 53 year old male

Reported by a health professional (non-physician/pharmacist) from France on 2007-01-26

Patient: 53 year old male weighing 50.0 kg (110.0 pounds)

Reactions: Hepatitis, Cardiac Arrest

Adverse event resulted in: death, life threatening event

Suspect drug(s):
Vfend
    Administration route: Oral
    Indication: Aspergillosis
    Start date: 2006-11-13
    End date: 2006-12-01

Moxifloxacin Hydrochloride
    Administration route: Oral
    Start date: 2006-11-07
    End date: 2006-12-01

Flagyl
    Administration route: Oral
    Start date: 2006-11-09
    End date: 2006-12-01

Possible Flagyl side effects / adverse reactions in 74 year old male

Reported by a consumer/non-health professional from Canada on 2007-01-29

Patient: 74 year old male

Reactions: Clostridium Difficile Colitis

Suspect drug(s):
Flagyl

Other drugs received by patient: Cardiovascular System Drugs; Cholesterol and Triglyceride Reducers

Possible Flagyl side effects / adverse reactions in 63 year old female

Reported by a health professional (non-physician/pharmacist) from Canada on 2007-01-29

Patient: 63 year old female

Reactions: Dyspnoea, Nasal Congestion, Throat Tightness, Rash Macular

Suspect drug(s):
Flagyl

Other drugs received by patient: Ampicillin; Gentamicin Sulfate; Dyazide; Losartan Potassium; Ventoline /00139501/; Atrovent; Beclomethasone Dipropionate

Possible Flagyl side effects / adverse reactions in 46 year old male

Reported by a individual with unspecified qualification on 2007-01-30

Patient: 46 year old male weighing 44.0 kg (96.8 pounds)

Reactions: Hyponatraemia, Hypokalaemia

Adverse event resulted in: hospitalization

Suspect drug(s):
Flagyl
    Indication: Lymphangitis
    Start date: 2006-03-24

Claforan
    Indication: Lymphangitis
    Start date: 2006-03-24

Cymevan /00784201/
    Indication: Cytomegalovirus Infection
    Start date: 2006-03-30
    End date: 2006-04-20

Pentasa
    Administration route: Oral

Kabiven
    Start date: 2006-03-13
    End date: 2006-04-20

Solu-Medrol
    Start date: 2006-03-09

Possible Flagyl side effects / adverse reactions in 53 year old male

Reported by a individual with unspecified qualification on 2007-01-31

Patient: 53 year old male

Reactions: Metabolic Acidosis, Coagulopathy, Cholestasis, Pyrexia, Hepatitis Cholestatic, Renal Failure, Sepsis, Circulatory Collapse, Leukocytosis, Cardiovascular Disorder

Adverse event resulted in: death, life threatening event

Suspect drug(s):
Flagyl
    Administration route: Oral
    Indication: Aspergillosis
    Start date: 2006-11-07
    End date: 2006-12-01

Moxifloxacin Hydrochloride
    Administration route: Oral
    Indication: Aspergillosis
    Start date: 2006-11-07
    End date: 2006-12-01

Vfend
    Administration route: Oral
    Indication: Aspergillosis
    Start date: 2006-11-13
    End date: 2006-12-01

Possible Flagyl side effects / adverse reactions in 46 year old male

Reported by a individual with unspecified qualification from France on 2007-02-01

Patient: 46 year old male

Reactions: Drug Ineffective, Colitis, Cytomegalovirus Infection, Hyponatraemia, Hypokalaemia

Adverse event resulted in: hospitalization

Suspect drug(s):
Pentasa
    Indication: Drug USE FOR Unknown Indication

Flagyl
    Dosage: 1500 mg daily, intravenous
    Indication: Infection
    Start date: 2006-03-24

Claforan
    Dosage: 3 g daily, intravenous
    Indication: Infection
    Start date: 2006-03-24

Cymeven (Ganciclovir Sodium)
    Dosage: 250 mg daily
    Indication: Cytomegalovirus Infection
    Start date: 2006-03-30
    End date: 2006-04-20

Kabiven (Amino Acids, Carbohydrates Nos, Electrolyes Nos, Fats Nos)
    Indication: Parenteral Nutrition
    Start date: 2006-03-31
    End date: 2006-04-20

Solu-Medrol
    Dosage: 60 mg daily, intravenous
    Indication: Colitis Ulcerative
    Start date: 2006-03-09

Possible Flagyl side effects / adverse reactions in 45 year old male

Reported by a physician from France on 2007-02-02

Patient: 45 year old male

Reactions: Blood Alkaline Phosphatase Increased, Blood Bilirubin Increased, Aspartate Aminotransferase Increased, Tendonitis, Mixed Hepatocellular-Cholestatic Injury

Suspect drug(s):
Tavanic
    Administration route: Oral
    Indication: Sigmoiditis
    Start date: 2007-01-01
    End date: 2007-01-01

Flagyl
    Administration route: Oral
    Indication: Sigmoiditis
    Start date: 2007-01-01

Other drugs received by patient: Acetaminophen

Possible Flagyl side effects / adverse reactions in 58 year old female

Reported by a health professional (non-physician/pharmacist) from France on 2007-02-02

Patient: 58 year old female weighing 83.0 kg (182.6 pounds)

Reactions: Renal Vasculitis, Cutaneous Vasculitis, Ileitis, Nephrotic Syndrome

Adverse event resulted in: hospitalization

Suspect drug(s):
Faslodex
    Indication: Breast Cancer Female
    Start date: 2006-06-01
    End date: 2006-06-01

Calcium Folinate Aguettant
    Indication: Breast Cancer Female
    Start date: 2006-03-07
    End date: 2006-05-18

Rocephin
    Start date: 2006-06-01
    End date: 2006-06-19

Ciprofloxacin
    Start date: 2006-06-20
    End date: 2006-07-04

Fluorouracil
    Indication: Breast Cancer Female
    Start date: 2006-03-07
    End date: 2006-05-18

Granocyte
    Start date: 2006-03-07
    End date: 2006-05-18

Flagyl
    Start date: 2006-06-01
    End date: 2006-07-04

Ametycine
    Indication: Breast Cancer Female
    Start date: 2006-03-07
    End date: 2006-05-18

Zofran
    Start date: 2006-03-07
    End date: 2006-05-18

Navelbine
    Indication: Breast Cancer Female
    Start date: 2006-03-07
    End date: 2006-05-18

Zometa
    Indication: Breast Cancer Female
    Start date: 2006-06-01
    End date: 2006-06-01

Possible Flagyl side effects / adverse reactions in 53 year old female

Reported by a consumer/non-health professional from Brazil on 2007-02-06

Patient: 53 year old female weighing 67.0 kg (147.4 pounds)

Reactions: Oral Intake Reduced, Oral Mucosal Blistering, Skin Injury, Swelling Face, Pain, Immunodeficiency, Skin Disorder, Pyrexia, Paraesthesia, Diarrhoea, Vasculitis

Adverse event resulted in: hospitalization, disablity

Suspect drug(s):
Flagyl
    Administration route: Oral
    Start date: 2006-08-03
    End date: 2006-08-09

Ciprofloxacin HCL
    Administration route: Oral
    Start date: 2006-08-03
    End date: 2006-08-09

Other drugs received by patient: Micardis; Pantoprazole Sodium; Ranitidine

Possible Flagyl side effects / adverse reactions in 53 year old male

Reported by a pharmacist from France on 2007-02-08

Patient: 53 year old male weighing 50.0 kg (110.0 pounds)

Reactions: Hepatitis Cholestatic

Adverse event resulted in: death, life threatening event

Suspect drug(s):
Moxifloxacin Hydrochloride
    Dosage: total daily dose: 400 mg unit dose: 400 mg
    Administration route: Oral
    Indication: Aspergillosis
    Start date: 2006-11-07
    End date: 2006-12-01

Flagyl
    Administration route: Oral
    Indication: Aspergillosis
    Start date: 2006-11-07
    End date: 2006-12-01

Vfend
    Dosage: unit dose: 200 mg
    Administration route: Oral
    Indication: Aspergillosis
    Start date: 2006-11-13
    End date: 2006-12-01

Other drugs received by patient: Xatral; Nicotinell; Motylio; Xanax

Possible Flagyl side effects / adverse reactions in 45 year old male

Reported by a physician from France on 2007-02-15

Patient: 45 year old male

Reactions: Tendonitis, Mixed Hepatocellular-Cholestatic Injury

Suspect drug(s):
Tavanic
    Administration route: Oral
    Indication: Sigmoiditis

Flagyl
    Administration route: Oral
    Indication: Sigmoiditis

Other drugs received by patient: Paracetamol

Possible Flagyl side effects / adverse reactions in 67 year old female

Reported by a physician from Canada on 2007-02-16

Patient: 67 year old female weighing 100.0 kg (220.0 pounds)

Reactions: Jaundice, Hyperbilirubinaemia, Chills, Pyrexia, Hepatitis, Abdominal Discomfort, Myalgia, Gamma-Glutamyltransferase Increased, Liver Function Test Abnormal, Oedema, Blood Alkaline Phosphatase Increased, Nausea, Chromaturia, Rash, Scleral Discolouration, Faeces Pale, Anorexia, Aspartate Aminotransferase Increased

Suspect drug(s):
Flagyl
    Administration route: Oral
    Start date: 1998-06-23
    End date: 1998-06-26

Arthrotec
    Administration route: Oral
    Indication: Arthritis
    Start date: 1998-06-10
    End date: 1998-06-26

Other drugs received by patient: Adalat; Losec /00661201/; Hydrochlorothiazide; Clinoril

Possible Flagyl side effects / adverse reactions in 49 year old male

Reported by a individual with unspecified qualification on 2007-02-16

Patient: 49 year old male

Reactions: Pain, Peripheral Sensory Neuropathy, Paraesthesia

Adverse event resulted in: hospitalization

Suspect drug(s):
Flagyl

Other drugs received by patient: Vaccines; Vaccines; Nexium