perphenazine vs thioridazine
PlainMeds reviewed this comparison against our methodology in August 2026. It places FDA and CMS record fields side by side, without recommending either medication.
Side-by-side comparison of perphenazine and thioridazine. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.
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Perphenazine is a medicine used to treat schizophrenia and control severe nausea and vomiting. It belongs to a class of drugs called typical antipsychotics.
Thioridazine is a medicine used to treat schizophrenia. It is only used when other antipsychotic medicines have not worked well enough.
Perphenazine is used to treat schizophrenia in adults. Schizophrenia is a mental illness that can affect how you think, feel, and behave. This medicine can also help control severe nausea and vomiting in adults.
Thioridazine is used to manage schizophrenia in adults and children. You should only use this medicine if other antipsychotic medicines have not worked for you. This is because thioridazine can cause serious heart problems.
Perphenazine works by changing the levels of certain natural chemicals in the brain. These chemicals, called neurotransmitters, help to regulate mood and behavior. By affecting these chemicals, perphenazine can help reduce symptoms of schizophrenia and control nausea.
Thioridazine affects the balance of certain chemicals in the brain. These chemicals, like dopamine, can affect mood and behavior. By changing the balance, thioridazine helps to reduce symptoms of schizophrenia.
- • Muscle stiffness or spasms
- • Restlessness
- • Slow movements
- • Shaking
- • Weight gain
- • Drowsiness
- • Dry mouth
- • Blurred vision
- • Constipation
- • Nausea
- Toxicity To Various Agents 274
- Weight Increased 222
- Akathisia 184
- Suicide Attempt 180
- Obsessive-Compulsive Disorder 163
- Weight Increased 8
- Dyspnoea 7
- Dystonia 6
- Hyperglycaemia 6
- Hypoxia 6
This medicine may increase the risk of death in elderly patients with dementia-related psychosis. Perphenazine is not approved to treat dementia-related psychosis. Talk to your doctor about the risks if you are an older adult with dementia.
Thioridazine can cause a life-threatening heart rhythm problem called Torsades de pointes, which can lead to sudden death. Because of this risk, only use thioridazine if other antipsychotic medicines have not worked. Elderly patients with dementia-related psychosis who are treated with antipsychotic drugs have an increased risk of death.
Tell your doctor if you are pregnant or plan to become pregnant. It is not known if perphenazine will harm an unborn baby. Talk to your doctor about the risks and benefits of taking this medicine while pregnant or breastfeeding.
Tell your doctor if you are pregnant or plan to become pregnant. It is not known if thioridazine will harm your unborn baby. Talk to your doctor about the risks and benefits of taking thioridazine during pregnancy and breastfeeding.
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How to Read This perphenazine vs thioridazine Comparison
perphenazine is classified in the Typical Antipsychotic (Phenothiazine) drug class, while thioridazine sits within the Typical Antipsychotic (Phenothiazine) class. Because both drugs share the same classification, they are often considered interchangeable in theory, but clinical outcomes rarely track that cleanly. 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, perphenazine has 1,023 submissions while thioridazine has 33. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. No direct interaction between these two drugs is listed in our FDA-derived dataset, though co-prescription still warrants pharmacist review. 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 perphenazine or thioridazine.
Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.