No

Antipsychotic Agent, Thioxanthene Derivative

Management of psychotic disorders

C

>10%:

Cardiovascular: Hypotension, orthostatic hypotension

Central nervous system: Pseudoparkinsonism, akathisia, dystonias, tardive dyskinesia (persistent), dizziness

Gastrointestinal: Constipation

Ocular: Pigmentary retinopathy

Respiratory: Nasal congestion

Miscellaneous: Decreased sweating

1% to 10%:

Dermatologic: Photosensitivity, skin rash

Endocrine & metabolic: Changes in menstrual cycle, changes in libido, pain in breasts

Gastrointestinal: Weight gain, nausea, vomiting, stomach pain

Genitourinary: Dysuria, ejaculatory disturbances

Neuromuscular & skeletal: Trembling of fingers

<1%:

Central nervous system: Neuroleptic malignant syndrome (NMS)

Dermatologic: discoloration of skin (blue-gray)

Endocrine & metabolic: Galactorrhea

Genitourinary: Priapism

Hematologic: Agranulocytosis, leukopenia

Hepatic: Cholestatic jaundice, hepatotoxicity

Ocular: Cornea and lens changes, pigmentary retinopathy

Miscellaneous: Impairment of temperature regulation lowering of seizures threshold

Decreased effect of guanethidine

Increased effect/toxicity: Alcohol, CNS depressants

Protect all dosage forms from light, clear or slightly yellow solutions may be used; should be dispensed in amber or opaque vials/bottles. Solutions may be diluted or mixed with fruit juices or other liquids but must be administered immediately after mixing; do not prepare bulk dilutions or store bulk dilutions.

The mechanism of action for chlorprothixene, like other thioxanthenes and phenothiazines, is not fully understood. The sites of action appear to be the reticular activating system of the midbrain, the limbic system, the hypothalamus, and the globus pallidus and corpus striatum. The mechanism appears to be one or more of a combination of postsynaptic blockade of adrenergic, dopaminergic, or serotonergic receptor sites, metabolic inhibition of oxidative phosphorylation, or decrease in the excitability of neuronal membranes.

Children >6 years: Oral: 10-25 mg 3-4 times/day

Adults:

Oral: 25-50 mg 3-4 times/day, to be increased as needed; doses exceeding 600 mg/day are rarely required

I.M.: 25-50 mg up to 3-4 times/day

I.M. dose is 4-10 times the activity of oral dose

No information available to require special precautions

Over 10% of dental patients may experience tardive dyskinesia and Parkinson-like syndromes; orthostatic hypotension is induced by chlorprothixene in over 10% of patients

May cause drowsiness; avoid alcohol

Concentrate, oral, as lactate and hydrochloride (fruit flavor): 100 mg/5 mL (480 mL)

Injection, as hydrochloride: 12.5 mg/mL (2 mL)

Tablet: 10 mg, 25 mg, 50 mg, 100 mg