Flagyl I.V. RTU (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 some patients.

Metronidazole is an antibiotic. It works by killing bacteria or stopping their growth. However, this medicine will not work for colds, flu, or other viral infections.

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

It is important for your doctor to monitor your progress while you are taking this medicine. This is to ensure that the infection is resolved. Blood tests may be necessary to check for side effects.

You should not receive metronidazole if you have taken disulfiram (Antabuse®) in the last 2 weeks. Combining these medicines can lead to serious side effects.

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

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

Reach out to your doctor right away if you feel burning, numbness, tingling, or pain in your arms, hands, legs, or feet. These might indicate a condition called peripheral neuropathy.

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

This medicine may increase your risk of serious liver problems, which could be life-threatening. This risk is higher if you have Cockayne syndrome (a rare form of dwarfism). Contact your doctor promptly if you have 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 occur 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 any other medicines unless you have discussed them with your doctor. This includes both prescription and 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 will make with your doctor. For this medicine, the following should be considered:

Allergies

Inform your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also, let your health care professional know if you have any 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 conducted to determine how age affects the effects of metronidazole injection in children. Safety and effectiveness have not been established.

Geriatric

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

Breast Feeding

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

Interactions with Medicines

Some medicines should not be used together at all, while in other cases, two different medicines may be used together even if an interaction might occur. In these situations, your doctor may want to adjust the dose or take other precautions. When 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 significance 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 adjust the dose or frequency of one or both 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 drugs may be necessary for your treatment. If both medicines are prescribed together, your doctor may adjust the dose or frequency of one or both medicines.

• Carbamazepine
• Cholestyramine
• Cyclosporine
• Milk Thistle

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be taken around the time of eating food or certain types of food due to possible interactions. Using alcohol or tobacco with certain medicines may also lead to interactions. The following interactions have been chosen based on their potential significance 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 the use of food, alcohol, or tobacco.

• Ethanol

Other Medical Problems

Having other medical problems may affect the use of this medicine. Be sure to inform 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 heightened due to slower removal of the medicine from the body.

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

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

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 may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or lessen 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 happen in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You can 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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