Metron/nacl 500mg Pb Inj, 100ml
WARNING: Metronidazole has been shown to cause cancer in mice and rats with long-term use. Talk with the doctor.The doctor has given you this drug for a certain health problem. Do not use this drug for other health problems. @ COMMON USES: It is used to treat infections.It is used to prevent infections during bowel surgery.It may be given to you for other reasons. Talk with the doctor.
Drug Class
Anti-infective, Antiprotozoal, Antibiotic
Pharmacologic Class
Nitroimidazole
Pregnancy Category
Category B
FDA Approved
Jun 1963
DEA Schedule
Not Controlled
Overview
What is this medicine?
Metronidazole is an antibiotic and anti-parasitic medication given through an IV (into your vein) to treat serious infections caused by certain types of bacteria and parasites. It works by stopping the growth of these germs.
How to Use This Medicine
Taking Your Medication
To use this medication correctly, follow your doctor's instructions and read all the information provided. It is essential to follow the dosage instructions carefully. This medication is administered as an infusion into a vein over a specified period.
Storing and Disposing of Your Medication
If you need to store this medication at home, consult with your doctor, nurse, or pharmacist to determine the proper storage procedure.
Missing a Dose
If you miss a dose, contact your doctor immediately to receive guidance on what to do next.
To use this medication correctly, follow your doctor's instructions and read all the information provided. It is essential to follow the dosage instructions carefully. This medication is administered as an infusion into a vein over a specified period.
Storing and Disposing of Your Medication
If you need to store this medication at home, consult with your doctor, nurse, or pharmacist to determine the proper storage procedure.
Missing a Dose
If you miss a dose, contact your doctor immediately to receive guidance on what to do next.
Lifestyle & Tips
- Avoid all alcohol and alcohol-containing products (e.g., cough syrups, mouthwash, aftershave) during treatment and for at least 3 days after stopping metronidazole. Combining them can cause severe nausea, vomiting, flushing, and headache (disulfiram-like reaction).
- Report any new or worsening numbness, tingling, pain, or weakness in your hands or feet immediately, as this could be a sign of nerve damage.
- Inform your doctor if you experience dizziness, confusion, or seizures.
- Your urine may turn dark or reddish-brown while on this medication; this is a harmless side effect.
- Complete the full course of treatment as prescribed, even if you start feeling better, to prevent the infection from returning and to reduce the risk of antibiotic resistance.
Available Forms & Alternatives
Available Strengths:
- Metronidazole 0.75% Topical Crm 45g
- Metronidazole 250mg Tablets
- Metronidazole 0.75% Topical Lotion
- Metron/nacl 500mg Pb Inj, 100ml
- Metronidazole 0.75% Vaginal Gel 70g
- Metronidazole 500mg Tablets
- Metronidazole 0.75% Topical Crm 45g
- Metronidazole 0.75% Topical Gel 45g
- Metronidazole 375mg Capsules
- Metronidazole 500mg Tablets
- Metronidazole 250mg Tablets
- Metronidazole 1% Topical Gel Pump
- Metronidazole 1% Topical Gel Tube
- Metronidazole 500mg/100ml Inj,100ml
- Metronidazole 0.75% Vaginal Gel 70g
Dosing & Administration
Adult Dosing
Standard Dose:
500 mg IV every 8 hours
Dose Range:
500 - 1000 mg
Condition-Specific Dosing:
Anaerobic Infections:
500 mg IV every 8 hours for 7-10 days, or longer depending on infection severity and site.
C. difficile Infection (severe):
500 mg IV every 8 hours for 10-14 days (often in combination with oral vancomycin).
Surgical Prophylaxis:
1500 mg IV as a single dose 30-60 minutes prior to surgery, or 500 mg IV 30-60 minutes prior to surgery followed by 500 mg IV every 8 hours for 1-2 doses post-op.
Pediatric Dosing
Neonatal:
Not established for routine use; consult infectious disease specialist. Dosing typically 7.5-15 mg/kg/day divided every 12-24 hours.
Infant:
7.5 mg/kg IV every 8 hours (max 500 mg/dose) for anaerobic infections.
Child:
7.5 mg/kg IV every 8 hours (max 500 mg/dose) for anaerobic infections.
Adolescent:
Same as adult dosing: 500 mg IV every 8 hours for anaerobic infections.
Dose Adjustments
Renal Impairment:
Mild:
No adjustment needed.
Moderate:
No adjustment needed.
Severe:
No adjustment needed for single dose or short course. For prolonged therapy, consider reducing dose by 50% or extending interval to every 12 hours.
Dialysis:
Hemodialysis removes metronidazole and its metabolites. Administer dose after hemodialysis on dialysis days. Peritoneal dialysis does not significantly remove metronidazole; no adjustment needed.
Hepatic Impairment:
Mild:
No adjustment needed.
Moderate:
Reduce dose by 30-50% in patients with severe hepatic impairment (Child-Pugh C). Monitor for adverse effects.
Severe:
Reduce dose by 50-75% in patients with severe hepatic impairment (Child-Pugh C). Monitor metronidazole levels if available, and observe closely for adverse effects.
Pharmacology
Mechanism of Action
Metronidazole is a prodrug that is activated by reduction of its nitro group by anaerobic bacteria and certain protozoa. This reduction forms reactive cytotoxic compounds that bind to and damage DNA, leading to inhibition of nucleic acid synthesis and cell death. It is bactericidal against susceptible organisms.
Pharmacokinetics
Absorption:
Bioavailability:
100% (for IV administration)
Tmax:
Not applicable for IV (peak concentration achieved rapidly after infusion)
FoodEffect:
Not applicable for IV
Distribution:
Vd:
0.51-1.1 L/kg
ProteinBinding:
Less than 20%
CnssPenetration:
Yes (achieves therapeutic concentrations in CSF, brain abscesses)
Elimination:
HalfLife:
6-8 hours (adults), 10-29 hours (neonates)
Clearance:
Not available (highly variable)
ExcretionRoute:
Renal (60-80%), Fecal (6-15%)
Unchanged:
Approximately 20% (renal)
Pharmacodynamics
OnsetOfAction:
Rapid (within minutes of IV infusion)
PeakEffect:
End of infusion
DurationOfAction:
Approximately 8 hours (based on dosing interval)
Confidence:
High
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
Although rare, this medication can cause severe and potentially life-threatening side effects. If you experience any of the following symptoms, contact your doctor immediately or seek emergency medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Redness or white patches in the mouth or throat
Vaginal itching or discharge
Fast or abnormal heartbeat
Pain when passing urine or blood in urine
Passing urine more often
Pelvic pain
Ringing in the ears, hearing loss, or other changes in hearing
Nervous System Problems
This medication can cause nervous system problems, especially with long-term use. If you experience any of the following symptoms, contact your doctor right away:
Burning, numbness, or tingling sensations that are not normal
Changes in balance or eyesight
Dizziness or fainting
Headache
Difficulty sleeping
Seizures
Trouble speaking
Confusion
Depression
Irritability
Fatigue
Weakness
Aseptic Meningitis
This medication may increase the risk of a severe brain problem called aseptic meningitis. If you experience any of the following symptoms, contact your doctor right away:
Headache
Fever
Chills
Severe stomach upset or vomiting
Stiff neck
Rash
Sensitivity to light
Feeling sleepy or confused
Low White Blood Cell Count
This medication can cause a decrease in white blood cell count, which may increase the risk of infection. If you experience any of the following symptoms, contact your doctor right away:
Fever
Chills
Sore throat
Severe Skin Reactions
This medication can cause severe skin reactions, including Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and other serious reactions. If you experience any of the following symptoms, seek medical help right away:
Red, swollen, blistered, or peeling skin
Red or irritated eyes
Sores in the mouth, throat, nose, eyes, genitals, or skin
Fever
Chills
Body aches
Shortness of breath
Swollen glands
Other Side Effects
Most people do not experience serious side effects, but some may occur. If you experience any of the following symptoms, contact your doctor if they bother you or do not go away:
Constipation
Diarrhea
Stomach pain
Upset stomach
Vomiting
Decreased appetite
Stomach cramps
Metallic taste
Headache
Joint pain
Decreased interest in sex
* Irritation at the injection site
Reporting Side Effects
If you have questions about side effects or want to report a side effect, contact your doctor or the FDA at 1-800-332-1088 or https://www.fda.gov/medwatch.
Although rare, this medication can cause severe and potentially life-threatening side effects. If you experience any of the following symptoms, contact your doctor immediately or seek emergency medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Redness or white patches in the mouth or throat
Vaginal itching or discharge
Fast or abnormal heartbeat
Pain when passing urine or blood in urine
Passing urine more often
Pelvic pain
Ringing in the ears, hearing loss, or other changes in hearing
Nervous System Problems
This medication can cause nervous system problems, especially with long-term use. If you experience any of the following symptoms, contact your doctor right away:
Burning, numbness, or tingling sensations that are not normal
Changes in balance or eyesight
Dizziness or fainting
Headache
Difficulty sleeping
Seizures
Trouble speaking
Confusion
Depression
Irritability
Fatigue
Weakness
Aseptic Meningitis
This medication may increase the risk of a severe brain problem called aseptic meningitis. If you experience any of the following symptoms, contact your doctor right away:
Headache
Fever
Chills
Severe stomach upset or vomiting
Stiff neck
Rash
Sensitivity to light
Feeling sleepy or confused
Low White Blood Cell Count
This medication can cause a decrease in white blood cell count, which may increase the risk of infection. If you experience any of the following symptoms, contact your doctor right away:
Fever
Chills
Sore throat
Severe Skin Reactions
This medication can cause severe skin reactions, including Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and other serious reactions. If you experience any of the following symptoms, seek medical help right away:
Red, swollen, blistered, or peeling skin
Red or irritated eyes
Sores in the mouth, throat, nose, eyes, genitals, or skin
Fever
Chills
Body aches
Shortness of breath
Swollen glands
Other Side Effects
Most people do not experience serious side effects, but some may occur. If you experience any of the following symptoms, contact your doctor if they bother you or do not go away:
Constipation
Diarrhea
Stomach pain
Upset stomach
Vomiting
Decreased appetite
Stomach cramps
Metallic taste
Headache
Joint pain
Decreased interest in sex
* Irritation at the injection site
Reporting Side Effects
If you have questions about side effects or want to report a side effect, contact your doctor or the FDA at 1-800-332-1088 or https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe nausea or vomiting
- Severe headache
- Dizziness or lightheadedness
- Confusion or hallucinations
- Seizures
- Numbness, tingling, pain, or weakness in hands or feet (peripheral neuropathy)
- Difficulty with coordination or walking (ataxia)
- Rash, hives, or itching
- Swelling of the face, lips, tongue, or throat (signs of allergic reaction)
- Yellowing of the skin or eyes (jaundice)
- Unusual bleeding or bruising
- Signs of a new infection (e.g., fever, sore throat, vaginal yeast infection)
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced.
If you have Cockayne syndrome, as some individuals with this condition have developed liver problems while taking this medication. In some cases, these liver issues have been severe, persistent, or even fatal.
If you have taken disulfiram within the past 14 days.
If you are less than 12 weeks pregnant, as this medication is not intended for use during this period.
This list is not exhaustive, and it is crucial to discuss all your medications (prescription, over-the-counter, natural products, and vitamins) and health issues with your doctor and pharmacist. They will help determine whether it is safe to take this medication in conjunction with your other treatments and health conditions. Never start, stop, or adjust the dosage of any medication without first consulting your doctor.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced.
If you have Cockayne syndrome, as some individuals with this condition have developed liver problems while taking this medication. In some cases, these liver issues have been severe, persistent, or even fatal.
If you have taken disulfiram within the past 14 days.
If you are less than 12 weeks pregnant, as this medication is not intended for use during this period.
This list is not exhaustive, and it is crucial to discuss all your medications (prescription, over-the-counter, natural products, and vitamins) and health issues with your doctor and pharmacist. They will help determine whether it is safe to take this medication in conjunction with your other treatments and health conditions. Never start, stop, or adjust the dosage of any medication without first consulting your doctor.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. Your doctor will also instruct you to have regular blood tests, so be sure to follow their guidance and discuss any concerns with them.
This medication may interfere with certain laboratory tests, so it is crucial to notify all your healthcare providers and laboratory personnel that you are taking this drug. If you are undergoing dialysis, consult with your doctor to discuss any necessary precautions.
To minimize potential interactions, you may need to avoid consuming alcohol or products containing alcohol or propylene glycol during treatment with this medication and for at least 72 hours after your last dose. Examples of products that may contain alcohol or propylene glycol include some cough syrups. Consuming these substances may cause adverse effects such as stomach cramps, nausea, vomiting, headaches, and flushing. Consult with your doctor to determine if you need to avoid alcohol or products containing alcohol or propylene glycol.
Do not exceed the recommended treatment duration, as this may increase the risk of a secondary infection. If you are following a low-sodium or sodium-free diet, consult with your doctor, as some formulations of this medication may contain sodium.
If you are 65 years or older, use this medication with caution, as you may be more susceptible to side effects. Pregnant or breastfeeding women, or those planning to become pregnant, should discuss the potential benefits and risks of this medication with their doctor to ensure informed decision-making.
This medication may interfere with certain laboratory tests, so it is crucial to notify all your healthcare providers and laboratory personnel that you are taking this drug. If you are undergoing dialysis, consult with your doctor to discuss any necessary precautions.
To minimize potential interactions, you may need to avoid consuming alcohol or products containing alcohol or propylene glycol during treatment with this medication and for at least 72 hours after your last dose. Examples of products that may contain alcohol or propylene glycol include some cough syrups. Consuming these substances may cause adverse effects such as stomach cramps, nausea, vomiting, headaches, and flushing. Consult with your doctor to determine if you need to avoid alcohol or products containing alcohol or propylene glycol.
Do not exceed the recommended treatment duration, as this may increase the risk of a secondary infection. If you are following a low-sodium or sodium-free diet, consult with your doctor, as some formulations of this medication may contain sodium.
If you are 65 years or older, use this medication with caution, as you may be more susceptible to side effects. Pregnant or breastfeeding women, or those planning to become pregnant, should discuss the potential benefits and risks of this medication with their doctor to ensure informed decision-making.
Overdose Information
Overdose Symptoms:
- Nausea
- Vomiting
- Ataxia (loss of coordination)
- Peripheral neuropathy (numbness, tingling)
- Seizures
What to Do:
There is no specific antidote for metronidazole overdose. Treatment is supportive and symptomatic. In case of suspected overdose, seek immediate medical attention or call a poison control center (e.g., 1-800-222-1222 in the US).
Drug Interactions
Contraindicated Interactions
- Alcohol (including alcohol-containing products like cough syrups, mouthwash) - due to disulfiram-like reaction
Major Interactions
- Warfarin (increased anticoagulant effect, increased bleeding risk)
- Disulfiram (psychotic reactions)
- Lithium (increased lithium levels, potential for toxicity)
- Busulfan (increased busulfan plasma concentrations, potential for toxicity)
Moderate Interactions
- Phenytoin (decreased metronidazole levels, increased phenytoin levels)
- Phenobarbital (decreased metronidazole levels)
- Cimetidine (increased metronidazole levels)
- Fluorouracil (increased fluorouracil toxicity)
- Cyclosporine (increased cyclosporine levels)
Minor Interactions
- Oral contraceptives (potential for reduced efficacy, though clinical significance is debated)
Monitoring
Baseline Monitoring
Liver function tests (ALT, AST, bilirubin)
Rationale: To assess baseline hepatic function, especially in patients with suspected or known hepatic impairment, as metronidazole is primarily metabolized by the liver.
Timing: Prior to initiation of therapy, particularly for prolonged courses or in patients with risk factors.
Complete Blood Count (CBC) with differential
Rationale: To establish baseline hematologic status, as metronidazole can rarely cause neutropenia or leukopenia, especially with prolonged use.
Timing: Prior to initiation of therapy, especially for prolonged courses.
Routine Monitoring
Clinical response to therapy
Frequency: Daily
Target: Resolution of signs and symptoms of infection
Action Threshold: Lack of improvement or worsening symptoms may indicate treatment failure, resistance, or alternative diagnosis.
Neurological assessment (e.g., for paresthesias, numbness, ataxia, seizures)
Frequency: Daily, especially with prolonged or high-dose therapy
Target: Absence of new or worsening neurological symptoms
Action Threshold: Development of neurological symptoms (e.g., peripheral neuropathy, seizures, encephalopathy) requires immediate discontinuation of metronidazole.
Liver function tests (ALT, AST, bilirubin)
Frequency: Weekly or bi-weekly for prolonged therapy, or as clinically indicated in patients with hepatic impairment.
Target: Within normal limits or stable for patient's baseline
Action Threshold: Significant elevation may warrant dose adjustment or discontinuation.
Complete Blood Count (CBC) with differential
Frequency: Weekly for prolonged therapy (>10-14 days)
Target: Within normal limits
Action Threshold: Significant decrease in white blood cell count (leukopenia, neutropenia) may necessitate discontinuation.
Symptom Monitoring
- Nausea
- Vomiting
- Diarrhea
- Metallic taste in mouth
- Headache
- Dizziness
- Peripheral neuropathy (numbness, tingling, pain in hands/feet)
- Seizures
- Ataxia (loss of coordination)
- Encephalopathy
- Aseptic meningitis
- Darkening of urine (harmless)
- Rash
- Fever
- Signs of superinfection (e.g., oral or vaginal candidiasis)
Special Patient Groups
Pregnancy
Metronidazole is classified as Pregnancy Category B. While animal studies have not shown harm to the fetus, adequate and well-controlled studies in pregnant women are lacking. It crosses the placenta. It is generally considered acceptable for use in the second and third trimesters when clearly needed, but its use in the first trimester is often avoided unless the benefits outweigh the potential risks.
Trimester-Specific Risks:
First Trimester:
Use generally avoided if possible due to theoretical concerns, though human data do not consistently show increased risk of birth defects. Consider alternative agents if available and effective.
Second Trimester:
Generally considered safe for use when indicated.
Third Trimester:
Generally considered safe for use when indicated.
Lactation
Metronidazole is excreted into breast milk in concentrations similar to maternal plasma levels. The American Academy of Pediatrics considers it compatible with breastfeeding, but some sources suggest potential for adverse effects in the infant (e.g., diarrhea, candidiasis, metallic taste).
Infant Risk:
L3 (Moderately Safe). Potential for infant exposure leading to gastrointestinal upset (diarrhea, candidiasis), metallic taste, or theoretical risk of carcinogenicity (though not proven in humans). A common recommendation is to pump and discard breast milk during treatment and for 12-24 hours after the last dose to minimize infant exposure, especially for single high doses.
Pediatric Use
Metronidazole IV is used in pediatric patients for specific anaerobic and protozoal infections. Dosing is weight-based. Neonates have prolonged half-life due to immature hepatic metabolism, requiring careful dosing and monitoring. Close monitoring for neurological adverse effects is important.
Geriatric Use
No specific dose adjustment is typically required based on age alone. However, elderly patients may have reduced hepatic or renal function, which could affect metronidazole clearance. Monitor for adverse effects, particularly neurological symptoms, and adjust dose if significant hepatic impairment is present.
Clinical Information
Clinical Pearls
- Metronidazole is highly effective against anaerobic bacteria and certain protozoa (e.g., Trichomonas, Giardia, Entamoeba). It is not effective against aerobic bacteria.
- The most common and important drug interaction is with alcohol, leading to a disulfiram-like reaction. Patients must be counselled to avoid all alcohol during and for at least 3 days after therapy.
- A metallic taste in the mouth is a very common and benign side effect.
- Peripheral neuropathy is a dose- and duration-dependent adverse effect. It is more common with prolonged or high-dose therapy and can be irreversible. Discontinue metronidazole if neurological symptoms develop.
- Metronidazole can cause darkening of the urine, which is a harmless metabolic byproduct.
- For C. difficile infection, oral vancomycin is generally preferred for severe cases, but IV metronidazole is an alternative or adjunctive therapy, especially if ileus is present.
Alternative Therapies
- Clindamycin (for anaerobic infections)
- Vancomycin (oral, for C. difficile infection)
- Tinidazole (another nitroimidazole, for some protozoal infections)
- Other broad-spectrum antibiotics with anaerobic coverage (e.g., carbapenems, piperacillin/tazobactam)
Cost & Coverage
Average Cost:
Highly variable, typically low per 500mg/100ml IV bag
Generic Available:
Yes
Insurance Coverage:
Tier 1 or 2 (Generic)
General Drug Facts
If your symptoms or health problems persist or worsen, it is essential to contact your doctor for further evaluation and guidance. To ensure safe and effective treatment, never share your medication with others, and do not take medication prescribed to someone else.
Store all medications in a secure location, out of the reach of children and pets, to prevent accidental ingestion. Dispose of unused or expired medications properly. Unless instructed otherwise, do not flush medications down the toilet or pour them down the drain. If you are unsure about the proper disposal method, consult your pharmacist for guidance. Many communities have drug take-back programs, which your pharmacist can help you locate.
Some medications may come with an additional patient information leaflet, so be sure to check with your pharmacist. If you have any questions or concerns about your medication, do not hesitate to discuss them with your doctor, nurse, pharmacist, or other healthcare provider.
In the event of a suspected overdose, immediately contact your local poison control center or seek emergency medical attention. Be prepared to provide information about the medication taken, including the amount and time of ingestion, to ensure prompt and effective treatment.
Store all medications in a secure location, out of the reach of children and pets, to prevent accidental ingestion. Dispose of unused or expired medications properly. Unless instructed otherwise, do not flush medications down the toilet or pour them down the drain. If you are unsure about the proper disposal method, consult your pharmacist for guidance. Many communities have drug take-back programs, which your pharmacist can help you locate.
Some medications may come with an additional patient information leaflet, so be sure to check with your pharmacist. If you have any questions or concerns about your medication, do not hesitate to discuss them with your doctor, nurse, pharmacist, or other healthcare provider.
In the event of a suspected overdose, immediately contact your local poison control center or seek emergency medical attention. Be prepared to provide information about the medication taken, including the amount and time of ingestion, to ensure prompt and effective treatment.