diazepam vs phenytoin
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Side-by-side comparison of diazepam and phenytoin. 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
Phenytoin There have also been reports that the metabolic elimination of phenytoin is decreased by diazepam.
Diazepam (Valium) is a medicine that can help with anxiety, muscle spasms, and seizures. It belongs to a class of drugs called benzodiazepines, which work by slowing down the brain.
Phenytoin injection is used to treat certain types of seizures. It can also prevent seizures during or after neurosurgery.
Diazepam can help manage anxiety disorders or provide short-term relief from anxiety symptoms. It can also relieve symptoms of alcohol withdrawal, such as shaking or agitation. Additionally, diazepam can help with muscle spasms and may be used with other medicines to treat seizures.
This medicine treats generalized tonic-clonic status epilepticus, a type of prolonged seizure. It also helps prevent and treat seizures that may happen during or after brain surgery. Sometimes, it can be used for a short time instead of the oral form of phenytoin when you cannot take the medicine by mouth.
Diazepam works by increasing the effects of a natural chemical in the brain called GABA. GABA helps to calm the brain and nerves. This can reduce anxiety, relax muscles, and prevent seizures.
Phenytoin works by slowing down the signals in the brain that cause seizures. It stabilizes nerve cell membranes, reducing excessive electrical activity. This helps to prevent seizures from starting or spreading.
- • Drowsiness
- • Fatigue
- • Muscle weakness
- • Uncoordinated movements
No common side effects listed.
- Toxicity To Various Agents 9,167
- Drug Abuse 7,019
- Nausea 6,149
- Fatigue 5,714
- Pain 5,202
- Drug Interaction 1,547
- Seizure 1,382
- Toxicity To Various Agents 1,353
- Convulsion 1,262
- Status Epilepticus 791
Diazepam can be habit-forming and can cause serious side effects, including breathing problems, coma, and even death, especially when taken with opioid pain medicines or alcohol. You should not stop taking diazepam suddenly, as this can cause withdrawal symptoms. Talk to your doctor about how to slowly stop taking diazepam.
This medicine can cause serious heart problems if given too quickly. The injection rate should not be faster than 50 mg per minute for adults, and 1 to 3 mg/kg/min (or 50 mg per minute, whichever is slower) for children. Your heart will be monitored closely during and after the injection.
Diazepam may harm an unborn baby. Talk to your doctor if you are pregnant or plan to become pregnant. It is not known if diazepam passes into breast milk, so talk to your doctor before breastfeeding.
Taking phenytoin during pregnancy may increase the risk of birth defects. If you are pregnant or plan to become pregnant, talk to your doctor about the risks and benefits of this medicine.
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How to Read This diazepam vs phenytoin Comparison
diazepam is classified in the Benzodiazepine drug class, while phenytoin sits within the Anticonvulsant (Hydantoin) 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, diazepam has 33,251 submissions while phenytoin has 6,335. 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 diazepam makes it harder for your body to get rid of phenytoin. this can cause the level of phenytoin in your blood to rise.. 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 diazepam or phenytoin.
Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.