metformin vs zonisamide
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Side-by-side comparison of metformin and zonisamide. 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
Examples: Topiramate, zonisamide, acetazolamide or dichlorphenamide.
Glucophage, Fortamet, Glumetza
Zonegran
No summary available.
Zonisamide is a medicine used with other medicines to treat partial seizures in adults with epilepsy. It belongs to a class of drugs called anticonvulsants.
Information not available.
Zonisamide is used to treat partial seizures in adults who have epilepsy. Epilepsy is a brain disorder that causes repeated seizures. This medicine is used along with other seizure medicines to help control your seizures.
Information not available.
Zonisamide works by slowing down the electrical signals in the brain that cause seizures. It is thought to stabilize nerve cell membranes, which reduces the chance of seizures. It may also affect certain chemicals in the brain.
- • Diarrhea
- • Upper respiratory tract infection (like a cold)
- • Headache
- • Feeling sleepy
- • Loss of appetite
- • Dizziness
- • Problems with coordination
- • Feeling agitated or irritable
- Nausea 21,946
- Diarrhoea 21,884
- Blood Glucose Increased 18,328
- Fatigue 17,252
- Acute Kidney Injury 16,440
- Seizure 1,574
- Fatigue 697
- Somnolence 645
- Convulsion 623
- Dizziness 558
No specific warnings noted.
If you are allergic to sulfonamide medicines, you should not take zonisamide. Using zonisamide with other medicines that also inhibit carbonic anhydrase (like topiramate) can increase the risk of metabolic acidosis, kidney stones, and high ammonia levels in the blood.
No pregnancy information available.
Tell your doctor if you are pregnant or plan to become pregnant. It is not known if zonisamide will harm your unborn baby. Talk to your doctor about the risks and benefits of taking zonisamide during pregnancy. It is also not known if zonisamide passes into breast milk, so talk to your doctor before breastfeeding.
How to Read This metformin vs zonisamide Comparison
metformin is classified in the Biguanide drug class, while zonisamide sits within the Anticonvulsant (Sulfonamide) 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, metformin has 95,850 submissions while zonisamide has 4,097. 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 zonisamide can cause your blood to become too acidic, which increases the risk of a rare but serious side effect when combined with metformin.. 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 metformin or zonisamide.
Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.