What is Thioridazine
Thioridazine is a piperidine phenothiazine that is structurally similar to mesoridazine, which is one of its metabolites.
It is used to treat psychotic disorders such as schizophrenia.
Thioridazine can produce a variety of cardiovascular adverse reactions, including dose-related QT prolongation and torsade de pointes (TdP).
Because of the potential for cardiovascular risks, the manufacturer recommends that therapy with thioridazine be reserved for patients who have failed to respond to adequate courses of treatment with at least 2 other antipsychotics, either because of inadequate efficacy or intolerable side effects.
As with all antipsychotics, the product label includes a boxed warning regarding an increased mortality risk in elderly patients with dementia-related psychosis. Thioridazine was originally approved by the FDA in 1959.
Brand Names
- Mellaril
- Mellaril-S
Indications & Dosage
- behavioral or psychological symptoms of dementia
- schizophrenia
For the treatment of schizophrenia in patients who fail to respond adequately to treatment with other antipsychotics
Side Effects
- agranulocytosis
- akathisia
- amenorrhea
- anaphylactoid reactions
- angioedema
- anorexia
- aplastic anemia
- appetite stimulation
- asphyxia
- atopic dermatitis
- blurred vision
- bradycardia
- breast enlargement
- bronchospasm
- cardiac arrest
- cerebral edema
- cholestasis
- confusion
- constipation
- contact dermatitis
- corneal opacification
- diarrhea
- dizziness
- drowsiness
- dysphagia
- dystonic reaction
- ejaculation dysfunction
- eosinophilia
- erythema
- exfoliative dermatitis
- fever
- galactorrhea
- glycosuria
- gynecomastia
- headache
- hemolytic anemia
- hepatitis
- hyperglycemia
- hyperhidrosis
- hyperprolactinemia
- hypersalivation
- hypertension
- hyperthermia
- hypoglycemia
- hyponatremia
- hypotension
- hypothermia
- ileus
- impotence (erectile dysfunction)
- infertility
- jaundice
- laryngeal edema
- lethargy
- leukopenia
- libido decrease
- lupus-like symptoms
- mastalgia
- menstrual irregularity
- miosis
- myasthenia
- mydriasis
- nasal congestion
- nausea
- neuroleptic malignant syndrome
- neutropenia
- orthostatic hypotension
- pallor
- pancytopenia
- parotitis
- peripheral edema
- photosensitivity
- polydipsia
- polyuria
- priapism
- pruritus
- pseudoparkinsonism
- psychosis
- purpura
- QT prolongation
- retinopathy
- seborrhea
- seizures
- SIADH
- sinus tachycardia
- skin hyperpigmentation
- stroke
- tardive dyskinesia
- thrombocytopenia
- torsade de pointes
- urinary incontinence
- urinary retention
- urticaria
- ventricular tachycardia
- visual impairment
- vomiting
- water intoxication
- weight gain
- xerostomia
Monitoring Parameters
- AIMS assessment
- CBC
- ECG
- ophthalmologic exam
- serum potassium
- serum prolactin
Contraindications
- abrupt discontinuation
- accidental exposure
- agranulocytosis
- alcoholism
- ambient temperature increase
- angina
- anticholinergic medications
- bone marrow suppression
- bradycardia
- breast cancer
- breast-feeding
- cardiac arrhythmias
- cardiac disease
- chemotherapy
- children
- closed-angle glaucoma
- CNS depression
- coadministration with other CNS depressants
- coma
- coronary artery disease
- dehydration
- dementia
- dental work
- diabetes mellitus
- driving or operating machinery
- dysphagia
- encephalopathy
- ethanol ingestion
- females
- fever
- geriatric
- GI obstruction
- head trauma
- heart failure
- hematological disease
- hepatic disease
- hyperprolactinemia
- hypertension
- hyperthermia
- hypokalemia
- hypomagnesemia
- hypotension
- hypothermia
- hypovolemia
- ileus
- infants
- infection
- infertility
- intracranial mass
- jaundice
- labor
- leukopenia
- long QT syndrome
- malnutrition
- myocardial infarction
- neonates
- neurological disease
- neutropenia
- obstetric delivery
- ocular disease
- orthostatic hypotension
- Parkinson’s disease
- phenothiazine hypersensitivity
- pregnancy
- pregnancy testing
- prostatic hypertrophy
- pulmonary disease
- QT prolongation
- radiographic contrast administration
- renal failure
- Reye’s syndrome
- seizure disorder
- seizures
- strenuous exercise
- stroke
- suicidal ideation
- sunlight (UV) exposure
- surgery
- tardive dyskinesia
- thyroid disease
- tobacco smoking
- torsade de pointes
- urinary retention
- vomiting
Interactions
- Abarelix
- Abiraterone
- Acarbose
- Acetaminophen; Butalbital
- Acetaminophen; Butalbital; Caffeine
- Acetaminophen; Butalbital; Caffeine; Codeine
- Acetaminophen; Caffeine; Dihydrocodeine
- Acetaminophen; Chlorpheniramine; Dextromethorphan; Phenylephrine
- Acetaminophen; Chlorpheniramine; Dextromethorphan; Pseudoephedrine
- Acetaminophen; Chlorpheniramine; Phenylephrine; Phenyltoloxamine
- Acetaminophen; Codeine
- Acetaminophen; Dextromethorphan; Doxylamine
- Acetaminophen; Dextromethorphan; Guaifenesin; Phenylephrine
- Acetaminophen; Dextromethorphan; Phenylephrine
- Acetaminophen; Dichloralphenazone; Isometheptene
- Acetaminophen; Diphenhydramine
- Acetaminophen; Guaifenesin; Phenylephrine
- Acetaminophen; Hydrocodone
- Acetaminophen; Oxycodone
- Acetaminophen; Pentazocine
- Acetaminophen; Propoxyphene
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- Aspirin, ASA; Carisoprodol; Codeine
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- Chlorpheniramine; Guaifenesin; Hydrocodone; Pseudoephedrine
- Chlorpheniramine; Hydrocodone
- Chlorpheniramine; Hydrocodone; Phenylephrine
- Chlorpheniramine; Hydrocodone; Pseudoephedrine
- Chlorpheniramine; Phenylephrine
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