metronidazole vs phenobarbital
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Side-by-side comparison of metronidazole and phenobarbital. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.
minor Known Drug Interaction
Drugs that Induce CYP450 Enzymes The simultaneous administration of drugs that induce microsomal liver enzymes, such as phenytoin or phenobarbital, may accelerate the elimination of metronidazole, resulting in reduced plasma levels; impaired clearance of phenytoin has also been reported.
Flagyl
Luminal
Metronidazole is an antibiotic medicine. It fights bacteria and certain parasites in your body.
Phenobarbital is a medicine that can help control seizures and calm you down. It belongs to a class of drugs called barbiturates.
Metronidazole treats infections like trichomoniasis, amebiasis, and certain anaerobic bacterial infections. Trichomoniasis is a sexually transmitted infection. Amebiasis includes infections of the intestines and liver. Anaerobic bacteria cause infections inside the abdomen, on the skin, and in the female reproductive system.
This medicine is used to treat generalized and partial seizures. Seizures are caused by unusual electrical activity in the brain. Phenobarbital helps to reduce this activity and prevent seizures.
Metronidazole works by entering the bacteria or parasite and damaging its DNA. This damage stops the bacteria or parasite from growing and multiplying. Eventually, the infection is cleared.
Phenobarbital works by slowing down the activity of your brain and nervous system. It increases the effects of a natural chemical in the body called GABA. This helps to reduce seizures and promote relaxation.
- • Nausea
- • Headache
- • Loss of appetite
- • Vomiting
- • Diarrhea
- • Drowsiness
- • Sedation
- • Lethargy
- • Vertigo
- Nausea 4,693
- Diarrhoea 4,116
- Vomiting 3,283
- Pyrexia 3,224
- Drug Hypersensitivity 3,138
- Seizure 1,534
- Drug Interaction 635
- Toxicity To Various Agents 621
- Status Epilepticus 482
- Multiple-Drug Resistance 442
Metronidazole can cause cancer in mice and rats. Only use it for the conditions listed in this leaflet. Do not drink alcohol or use products with propylene glycol while taking this medicine, and for 3 days after.
You should not take this medicine if you are allergic to barbiturates. Also, do not take it if you have a history of porphyria, severe liver problems, or breathing problems.
Do not take metronidazole during the first three months of pregnancy. Talk to your doctor if you are pregnant or breastfeeding before taking this medicine.
Tell your doctor if you are pregnant or plan to become pregnant. Phenobarbital can harm an unborn baby. Talk to your doctor about the risks and benefits of taking this medicine while breastfeeding.
Also Compare, Nearby Drugs
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How to Read This metronidazole vs phenobarbital Comparison
metronidazole is classified in the Nitroimidazole Antibiotic drug class, while phenobarbital sits within the Anticonvulsant (Barbiturate) class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are prescription-only, so a licensed provider must authorize use.
Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, metronidazole has 18,454 submissions while phenobarbital has 3,714. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. These two drugs have a known minor interaction flagged in FDA labeling, attributed to phenobarbital makes your liver break down metronidazole faster than normal. this can lower the amount of medicine in your blood and make it less effective at fighting infections.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.
A table cannot represent individual circumstances. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This registry does not provide medical, treatment, substitution, or medication-change directions for metronidazole or phenobarbital.
Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.