Thiothixene
Thiothixene (Navane)
Thiothixene
(thigh-oh- THICKS-een)
Pregnancy Category: C Navane Thiothixene HCl Intensol (Rx)

Classification: Antipsychotic, miscellaneous

Action/Kinetics: Mechanism of action may be due to blockade of postsynaptic dopamine receptors in the brain, especially at subcortical levels in the reticular formation, hypothalamus, and limbic system. Also causes cholinergic and alpha-adrenergic blocking effects, adrenergic potentiating effects, antiserotonin effects, and prevention of uptake of biogenic amines. This results in significant extrapyramidal symptoms and antiemetic effects and minimal sedation, orthostatic hypotension, and anticholinergic symptoms. The margin between a therapeutically effective dose and one that causes extrapyramidal symptoms is narrow. Well absorbed from the GI tract. Peak plasma levels, PO: 1-3 hr. t 1/2: 34 hr. A therapeutic response may occur within 1 to 6 hr following IM use and within a few days to several weeks following PO use. Metabolized in the liver and excreted in the feces as both unchanged drug and metabolites.

Uses: Symptomatic treatment of psychotic disorders, including withdrawn, apathetic schizophrenia, delusions, and hallucinations.

Contraindications: Use in clients with circulatory collapse, comatose states, CNS depression due to any cause, and blood dyscrasias. Hypersensitivity to thiothixene and possibly phenothiazine derivatives. Use in children less than 12 years of age.

Special Concerns: Use with caution in CV disease, glaucoma, and prostatic hypertrophy, and in those exposed to extreme heat. Use with extreme caution in those with a history of seizure disorders, alcohol withdrawal, and in clients who develop akathisia and restlessness. Use during pregnancy only when potential benefits outweigh possible risks to the mother and/or fetus.

Side Effects: Since thiothixene has pharmacologic properties similar to phenothiazines, the side effects associated with phenothiazines should also be consulted. CNS: Drowsiness, extrapyramidal symptoms (especially akathisia and dystonia), persistent tardive dyskinesia (especially in female geriatric clients), lethargy, dizziness, restlessness, lightheadedness, agitation, insomnia, hyperpyrexia, weakness, fatigue. Rarely, seizures and paradoxical exacerbation of psychoses. GI: Dry mouth constipation, increased salivation, adynamic ileus, anorexia, N&V;, diarrhea, increase in appetite and weight, cholestatic jaundice. CV: Orthostatic hypotension, tachycardia, syncope, ECG changes. Ophthlamic: Blurred vision, miosis, mydriasis. Hypersensitivity: Rash, pruritus, urticaria, photosensitivity, anaphylaxis (rare). GU: Impotence, lactation, moderate breast enlargement in women, amenorrhea. Hematologic: Leukopenia, leukocytosis. Miscellaneous: Neuroleptic malignant syndrome. Increased sweating, nasal congestion, impotence, leg cramps, polydypsia, peripheral edema, fine lenticular pigmentation.

Laboratory Test Alterations: Serum transaminase, alkaline phosphatase, uric acid excretion. Prothrombin time.

Overdose Management: Symptoms: Muscle twitching, drowsiness, dizziness. In severe cases, symptoms include rigidity, weakness, torticollis, tremor, salivation, dysphagia, disturbance of gait, CNS depression, coma. Treatment: General supportive measures, including maintaining an adequate airway and oxygenation. Gastric lavage, if overdose found early. Hypotension and circulatory collapse may be treated with IV fluids and/or vasopressor agents (epinephrine is not to be used). Antiparkinson drugs may be used to treat extrapyramidal symptoms. Do not use analeptic drugs.

Drug Interactions: Anticholinergic drugs / Additive or potentiation of anticholinergic effect CNS depressants / Additive or potentiation of depressant effect Hypotensive drugs / Additive or potentiation of hypotensive effect

How Supplied: Capsules: 1 mg, 2 mg, 5 mg, 10 mg, 20 mg; Concentrate: 5 mg/mL

Dosage
?Capsules, Concentrate Mild to moderate psychoses.
Adults, initial: 2 mg t.i.d., increased to 15 mg/day if necessary.
Severe psychoses.
Adults, initial: 5 mg b.i.d., increased to 60 mg/day if necessary. The usual optimum dose is 20-30 mg/day. Doses greater than 60 mg/day rarely increase the therapeutic effect.