Flagyl I.V. (Intravenous)

Metronidazole injection is used to treat serious bacterial infections in various parts of the body. It is also used to prevent infections in the bowels before and after surgery for certain patients.

Metronidazole is part of a group of medicines called antibiotics. It works by killing bacteria or stopping them from growing. However, this medicine will not work for colds, flu, or other viral infections.

This medicine must only be given by or under the direct supervision of your doctor.

It is important for your doctor to monitor your progress while you are using this medicine. This is to ensure that the infection is gone. You may need blood tests to check for side effects.

You should not use metronidazole if you have taken disulfiram (Antabuse®) in the last 2 weeks. Taking these medicines together may lead to serious side effects.

Drinking alcohol while you are using this medicine may cause stomach pain, nausea, vomiting, headache, or flushing or redness of the face. Other products that contain alcohol (like elixirs, cough syrups, tonics) may also lead to problems. This medicine may also make alcoholic beverages taste different. You should not drink alcohol or use other alcohol-containing products while you are on this medicine and for at least 3 days after stopping it.

Contact your doctor immediately if you experience dizziness, problems with muscle control or coordination, shakiness or an unsteady walk, slurred speech, or difficulty speaking. These may be signs of a serious brain condition called encephalopathy.

Contact your doctor right away if you have burning, numbness, tingling, or painful feelings in the arms, hands, legs, or feet. These could be signs of a condition called peripheral neuropathy.

Call your doctor immediately if you have confusion, drowsiness, fever, a general feeling of being unwell, a headache, loss of appetite, nausea, a stiff neck or back, or vomiting. These could be signs of a serious condition called aseptic meningitis.

This medicine may increase your risk of serious liver problems, which can be life-threatening. This risk is higher if you have Cockayne syndrome (a rare form of dwarfism). Contact your doctor right away if you experience pain or tenderness in the upper stomach, pale stools, dark urine, loss of appetite, nausea, vomiting, or yellowing of the eyes or skin.

Serious skin reactions can happen with this medicine. Contact your doctor immediately if you notice blistering, peeling, or loosening of the skin, red skin lesions, severe acne or a skin rash, sores or ulcers on the skin, or fever or chills while using this medicine.

Do not take other medicines unless you have talked about them with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines, as well as herbal or vitamin supplements.

In deciding to use a medicine, the risks of taking the medicine must be weighed against the benefits it will provide. This is a decision you and your doctor will make together. For this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also, inform your healthcare professional if you have other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies have not been performed on the relationship of age to the effects of metronidazole injection in children. Safety and effectiveness have not been established.

Geriatric

Appropriate studies conducted so far have not shown specific problems in elderly patients that would limit the usefulness of metronidazole injection in older adults. However, elderly patients are more likely to experience unwanted effects and may have age-related liver, kidney, or heart issues, which may require caution and a dose adjustment for those receiving metronidazole injection.

Breast Feeding

There are no adequate studies in women to determine the risk to infants when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Interactions with Medicines

While some medicines should not be used together at all, in other cases, two different medicines may be used together even if an interaction might happen. In these situations, your doctor might want to adjust the dose, or other precautions may be necessary. When you are receiving this medicine, it is especially important that your healthcare professional knows if you are taking any of the medicines listed below. The following interactions have been chosen based on their potential importance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.

• Amprenavir
• Bepridil
• Cisapride
• Disulfiram
• Dronabinol
• Dronedarone
• Levoketoconazole
• Mesoridazine
• Pimozide
• Saquinavir
• Sparfloxacin
• Terfenadine
• Thioridazine
• Ziprasidone

Using this medicine with any of the following medicines is usually not recommended, but may be necessary in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

• Acenocoumarol
• Adagrasib
• Alfuzosin
• Amiodarone
• Amitriptyline
• Anagrelide
• Apomorphine
• Aripiprazole
• Aripiprazole Lauroxil
• Arsenic Trioxide
• Asenapine
• Astemizole
• Atazanavir
• Azithromycin
• Bedaquiline
• Buprenorphine
• Bupropion
• Buserelin
• Busulfan
• Capecitabine
• Ceritinib
• Chloroquine
• Chlorpromazine
• Cholera Vaccine, Live
• Cimetidine
• Ciprofloxacin
• Citalopram
• Clarithromycin
• Clofazimine
• Clomipramine
• Clothiapine
• Clozapine
• Crizotinib
• Cyclobenzaprine
• Dabrafenib
• Dasatinib
• Degarelix
• Delamanid
• Desipramine
• Deslorelin
• Deutetrabenazine
• Dexmedetomidine
• Disopyramide
• Dofetilide
• Dolasetron
• Domperidone
• Donepezil
• Doxepin
• Doxifluridine
• Droperidol
• Ebastine
• Efavirenz
• Encorafenib
• Entrectinib
• Eribulin
• Erythromycin
• Escitalopram
• Famotidine
• Felbamate
• Fexinidazole
• Fingolimod
• Flecainide
• Fluconazole
• Fluorouracil
• Fluoxetine
• Formoterol
• Foscarnet
• Fosphenytoin
• Galantamine
• Gatifloxacin
• Gemifloxacin
• Glasdegib
• Gonadorelin
• Goserelin
• Granisetron
• Halofantrine
• Haloperidol
• Histrelin
• Hydroquinidine
• Hydroxychloroquine
• Hydroxyzine
• Ibutilide
• Iloperidone
• Imipramine
• Inotuzumab Ozogamicin
• Itraconazole
• Ivabradine
• Ivosidenib
• Ketoconazole
• Lapatinib
• Leuprolide
• Levofloxacin
• Lithium
• Lofexidine
• Lumefantrine
• Macimorelin
• Mebendazole
• Mefloquine
• Methadone
• Methotrimeprazine
• Mifepristone
• Mizolastine
• Mobocertinib
• Moricizine
• Moxifloxacin
• Mycophenolate Mofetil
• Mycophenolic Acid
• Nafarelin
• Nelfinavir
• Nilotinib
• Norfloxacin
• Octreotide
• Ofloxacin
• Olanzapine
• Ondansetron
• Osimertinib
• Oxaliplatin
• Ozanimod
• Pacritinib
• Paliperidone
• Panobinostat
• Papaverine Hydrochloride
• Paroxetine
• Pasireotide
• Pazopanib
• Pentamidine
• Perphenazine
• Phenobarbital
• Phenprocoumon
• Phenytoin
• Pimavanserin
• Pipamperone
• Piperaquine
• Pitolisant
• Ponesimod
• Posaconazole
• Primidone
• Probucol
• Procainamide
• Prochlorperazine
• Promethazine
• Propafenone
• Protriptyline
• Quetiapine
• Quinidine
• Quinine
• Ranolazine
• Relugolix
• Ribociclib
• Risperidone
• Ritonavir
• Selpercatinib
• Sertindole
• Sertraline
• Sevoflurane
• Siponimod
• Sodium Phosphate
• Sodium Phosphate, Dibasic
• Sodium Phosphate, Monobasic
• Solifenacin
• Sorafenib
• Sotalol
• Sulpiride
• Sultopride
• Sunitinib
• Tacrolimus
• Tamoxifen
• Tegafur
• Telaprevir
• Telavancin
• Telithromycin
• Tetrabenazine
• Tolterodine
• Toremifene
• Trazodone
• Trimipramine
• Triptorelin
• Vandetanib
• Vardenafil
• Vemurafenib
• Venlafaxine
• Vilanterol
• Vinflunine
• Voclosporin
• Voriconazole
• Vorinostat
• Warfarin
• Zotepine
• Zuclopenthixol

Using this medicine with any of the following medicines may increase the risk of certain side effects, but using both medications may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

• Carbamazepine
• Cholestyramine
• Cyclosporine
• Milk Thistle

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used at or around the time of eating food or certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions. The following interactions have been chosen based on their potential importance and are not necessarily all-inclusive.

Using this medicine with any of the following is not recommended. Your doctor may decide not to treat you with this medication, change some of the other medicines you take, or give you special instructions about using food, alcohol, or tobacco.

• Ethanol

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

• Blood or bone marrow problems, or history of or
• Brain disease (e.g., aseptic meningitis, encephalopathy) or
• Edema (too much fluid in the body) or
• Leukopenia (low white blood cells), history of or
• Optic neuropathy (eye disease with vision changes), history of or
• Oral thrush (Candida infection) or
• Peripheral neuropathy (nerve problem), history of or
• Seizures, history of or
• Vaginal yeast infection (Candida infection)—Use with caution. May worsen these conditions.

• Kidney disease, end-stage or
• Liver disease, severe—Use with caution. The effects may be increased due to slower removal of the medicine from the body.

Along with its necessary effects, a medicine can cause some unwanted effects. Not all of these side effects may happen, but if they do, they might need medical attention.

Check with your doctor or nurse right away if you notice any of the following side effects:

More common

• Agitation
• back pain
• blindness
• blurred vision
• burning, crawling, itching, numbness, pain, prickling, "pins and needles", or tingling feelings
• change in taste
• clay-colored stools
• confusion
• dark-colored urine
• decreased vision
• dizziness
• drowsiness
• eye pain
• fever
• headache
• irritability
• itching of the vagina or outside genitals
• light-colored stools
• loss of appetite
• loss of taste
• mood or mental changes
• nausea
• pain during sexual intercourse
• seeing or hearing things that are not there
• seizures
• stiff neck or back
• stomach pain
• thick, white curd-like vaginal discharge without odor or with mild odor
• uncontrolled eye movements
• unpleasant breath odor
• unsteadiness or awkwardness
• unusual tiredness or weakness
• vomiting
• vomiting of blood
• weakness in the arms, hands, legs, or feet
• yellow eyes or skin

Incidence not known

• Black, tarry stools
• blistering, peeling, or loosening of the skin
• changes in skin color
• changes in speech patterns
• chest pain
• chills
• cough
• diarrhea
• fainting
• fast, pounding, or irregular heartbeat or pulse
• feeling of warmth
• itching
• joint or muscle pain
• lower back or side pain
• pain, tenderness, or swelling of the foot or leg
• painful or difficult urination
• pale skin
• red skin lesions, often with a purple center
• red, irritated eyes
• redness of the face, neck, arms, and occasionally, upper chest
• shakiness and unsteady walk
• slurred speech
• sore throat
• sores, ulcers, or white spots in the mouth or on the lips
• trouble with speaking
• unsteadiness, trembling, or other problems with muscle control or coordination
• unusual bleeding or bruising

Some side effects may happen that usually do not need medical attention. These side effects might go away as your body adjusts to the medicine. Additionally, your health care professional may have ways to help prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome, or if you have any questions about them:

Incidence not known

• Dry mouth
• hives or welts, skin rash
• redness of the skin
• stomach discomfort
• stuffy nose
• unpleasant metallic taste

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

In the U.S.

• Flagyl I.V.
• Flagyl I.V. RTU

Available Dosage Forms:

• Solution

Therapeutic Class: Antibiotic

Chemical Class: Nitroimidazole

A nurse or other trained health professional will give you this medicine in a hospital. It is given through a needle placed into one of your veins.

Your doctor will give you a few doses of this medicine until your condition improves, and then switch you to an oral medicine that works the same way. If you have any concerns about this, talk to your doctor.

• What happens if you drink alcohol with metronidazole?
• What are the most common skin conditions? (with photos)
• How long does it take for metronidazole to work?
• Is metronidazole safe for dogs? Uses, dosage, side effects?
• Does Flagyl (metronidazole) treat UTI infections?
• What can I do about the metallic taste of Flagyl?
• Can metronidazole cause a yeast infection?
• Can you have sex while taking metronidazole?
• Does metronidazole treat chlamydia?

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