Loxapac


loxapine succinate

Apo-Loxapine (CA), Dom-Loxapine (CA), Loxapac (CA), Nu-Loxapine (CA), PHL-Loxapine (CA), PMS-Loxapine (CA)

Pharmacologic class: Tricyclic dibenzoxazepine derivative

Therapeutic class: Antipsychotic

Pregnancy risk category C

Action

Unknown. Thought to block neurotransmission of postsynaptic dopamine receptors in brain, alleviating psychotic symptoms.

Availability

Capsules: 5 mg, 10 mg, 25 mg, 50 mg

Indications and dosages

Schizophrenia

Adults: 10 mg P.O. b.i.d. Dosage may be increased over first 7 to 10 days, up to 100 mg/day P.O. in two to four divided doses. Maximum dosage is 250 mg/day.

Dosage adjustment

• Elderly patients

Contraindications

• Hypersensitivity to drug or other dibenzoxazepines

• Coma or severe drug-induced CNS depression

Precautions

Use cautiously in:

• seizures, cerebral arteriosclerosis, severe hypotension, hypertension, glaucoma, breast cancer, hepatic disease, bone marrow depression, Parkinson's disease, blood dyscrasias, urinary retention, concurrent use of other CNS active drugs or anticholinergics

• pregnant or breastfeeding patients

• children younger than age 16.

Administration

• Give with or without food.

Adverse reactions

CNS: drowsiness, insomnia, vertigo, headache, dizziness, weakness, akinesia, staggering or shuffling gait, slurred speech, agitation, extrapyramidal reactions, sedation, syncope, tardive dyskinesia, numbness, confusion, pseudoparkinsonism, EEG changes, seizures, neuroleptic malignant syndrome

CV: orthostatic hypotension, hypertension, ECG changes

EENT: blurred vision, ptosis, nasal congestion

GI: nausea, vomiting, constipation, dry mouth, paralytic ileus

GU: urinary retention

Hematologic: leukopenia, agranulocytosis, thrombocytopenia

Hepatic: hepatocellular injury with hepatic enzyme elevations

Metabolic: polydipsia

Musculoskeletal: muscle twitching

Skin: rash, pruritus, seborrhea, photosensitivity, alopecia

Other: weight gain or loss, hyperpyrexia, facial edema, hypersensitivity reactions

Interactions

Drug-drug. Anticholinergics, CNS depressants: additive effects

Epinephrine: severe hypotension, tachycardia, decreased epinephrine effects

Drug-diagnostic tests. Granulocytes, platelets, white blood cells: decreased counts

Liver function tests: increased values

Drug-behaviors. Alcohol use: increased CNS depression

Patient monitoring

• Measure blood pressure before and periodically during therapy.

• Monitor hematologic studies and liver function tests.

See Stay alert for evidence of neuroleptic malignant syndrome (extrapyramidal symptoms, hyperpyrexia, muscle rigidity, altered mental status, irregular pulse or blood pressure, tachycardia, arrhythmias, diaphoresis).

• Assess for tardive dyskinesia (involuntary jerky movements of face, tongue, jaws, trunk, arms, and legs), especially in elderly women.

Patient teaching

• Tell patient to take with or without food.

• Inform patient that drug may cause tardive dyskinesia. Describe symptoms.

• Caution patient to avoid activities requiring mental concentration until drug's effects are known.

See Teach patient to immediately report sore throat, fever, rash, impaired vision, tremors, involuntary muscle twitching, muscle stiffness, or yellowing of eyes or skin.

• Instruct patient to move slowly when sitting up or standing, to avoid dizziness from sudden blood pressure decrease.

• Caution patient to avoid alcohol use.

• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, and behaviors mentioned above.

loxapine

(lox-a-peen) loxapine,

Loxapac

(trade name),

Loxitane

(trade name),

Xylac

(trade name)

Classification

Therapeutic: antipsychotics
Pregnancy Category: C

Indications

Schizophrenia.Considered second-line treatment after failure of atypical antipsychotic.Other psychotic disorders.Bipolar disorder.

Action

Appears to block dopamine and serotonin at postsynaptic receptor sites in the CNS.

Therapeutic effects

Diminution of psychotic behavior.

Pharmacokinetics

Absorption: Bioavailability is approximately 30%.Distribution: Unknown.Metabolism and Excretion: Extensively metabolized by the liver; some conversion to active antipsychotic compounds.Half-life: 3–4 hr.

Time/action profile (antipsychotic effect)

ROUTEONSETPEAKDURATION
PO30 min1.5–3 hr12 hr

Contraindications/Precautions

Contraindicated in: Hypersensitivity or intolerance to loxapine or amoxapine; Coma; CNS depression; Obstetric: Safety not established; weigh potential benefit against possible risks to fetus; Lactation: Discontinue drug or bottle-feed.Use Cautiously in: Glaucoma; Intestinal obstruction; History of seizures; Alcohol use disorder; Cardiovascular disease; Impaired liver function; Geriatric men or men with prostatic hyperplasia (more prone to urinary retention); Geriatric: More susceptible to adverse reactions; ↑ risk of mortality in elderly patients treated for dementia-related psychosis; Pediatric: Safety not established.

Adverse Reactions/Side Effects

Central nervous system

  • neuroleptic malignant syndrome (life-threatening)
  • confusion (most frequent)
  • dizziness (most frequent)
  • drowsiness (most frequent)
  • extrapyramidal reactions
  • headache
  • insomnia
  • syncope
  • tardive dyskinesia
  • weakness

Ear, Eye, Nose, Throat

  • blurred vision (most frequent)
  • lens opacities
  • nasal congestion

Cardiovascular

  • orthostatic hypotension (most frequent)
  • tachycardia

Gastrointestinal

  • constipation
  • drug-induced hepatitis
  • dry mouth
  • ileus
  • nausea
  • vomiting

Genitourinary

  • urinary retention

Dermatologic

  • dermatitis
  • edema
  • facial photosensitivity
  • pigment changes
  • rashes
  • seborrhea

Endocrinologic

  • galactorrhea

Hematologic

  • agranulocytosis (life-threatening)

Neurologic

  • ataxia

Miscellaneous

  • allergic reactions

Interactions

Drug-Drug interaction

Blocks the alpha-adrenergic effects of epinephrine (may result in hypotension and tachycardia).Additive CNS depression with other CNS depressants, including alcohol, antihistamines, opioid analgesics, and sedative/hypnotics.Antacids or adsorbent antidiarrheals may ↓ absorption.Use with antidepressants or MAO inhibitors may result in prolonged CNS depression and ↑ anticholinergic effects.Concomitant use of kava, valerian, skullcap, chamomile, or hops can ↑ CNS depression.

Route/Dosage

Oral (Adults) 10 mg twice daily, may be ↑ gradually over the first 7–10 days as needed and tolerated. Usual maintenance dose is 60–100 mg/day.

Availability (generic available)

Capsules: 5 mg, 10 mg, 25 mg, 50 mg Tablets: 5 mg, 10 mg, 25 mg, 50 mg

Nursing implications

Nursing assessment

  • Monitor patient’s mental status (orientation, mood, behavior) before and periodically during therapy.
  • Assess positive (delusions, hallucinations, agitation) and negative (social withdrawal) symptoms of schizophrenia.
  • Assess weight and BMI initially and throughout therapy. Refer as appropriate for nutritional/weight management and medical management.
  • Monitor BP (sitting, standing, lying) and pulse rate before and frequently during.dose adjustment.
  • Observe patient carefully when administering medication to ensure that medication is actually taken and not hoarded or cheeked.
  • Monitor patient for onset of akathisia (restlessness or desire to keep moving) and extrapyramidal side effects (parkinsonian—difficulty speaking or swallowing, loss of balance control, pill rolling of hands, mask-like face, shuffling gait, rigidity, tremors; and.dystonic—muscle spasms, twisting motions, twitching, inability to move eyes, weakness of arms or legs) every 2 mo during therapy and 8–12 wk after therapy has been discontinued. Report these symptoms; reduction in dosage or discontinuation of medication may be necessary. Trihexyphenidyl, diphenhydramine, or benzotropine may be used to control symptoms. Benzodiazepines may alleviate akathisia.
  • Monitor for tardive dyskinesia (uncontrolled rhythmic movement of mouth, face, and extremities; lip smacking or puckering; puffing of cheeks; uncontrolled chewing; rapid or worm-like movements of tongue, excessive eye blinking). Tardive dyskinesia is dose related initially but may increase with cumulative dose. Report immediately; may be irreversible.
  • Monitor frequency and consistency of bowel movements. Increasing bulk and fluids in the diet may help minimize constipation.
  • Loxapine lowers the seizure threshold. Institute seizure precautions for patients with history of seizures.
  • Monitor for development of neuroleptic malignant syndrome (fever, respiratory distress, tachycardia, convulsions, diaphoresis, hypertension or hypotension, pallor, tiredness, severe muscle stiffness, loss of bladder control). Report symptoms immediately.
  • Lab Test Considerations: Monitor CBC and differential before and periodically throughout therapy.
    • Obtain fasting blood glucose and cholesterol levels initially and periodically during therapy.
    • Monitor liver function studies and urine bilirubin and bile concentrations if patient develops jaundice.
  • Antiemetic effects of loxapine may block the action of ipecac. Overdose is treated by gastric lavage, barbiturates to control seizures, and supportive care for fluctuations in body temperature. Hypotension may be corrected by use of IV fluids, norepinephrine, or phenylephrine. Avoid use of epinephrine, as it may worsen hypotension.

Potential Nursing Diagnoses

Disturbed thought process (Indications)
Disturbed sensory perception(specify: visual, auditory, kinesthetic, gustatory, tactile, or olfactory) (Indications)

Implementation

  • Do not confuse loxapine (Loxitane) with acetretin (Soriatane), Lexapro (escitalopram), or fluoxetine (Prozac).
  • Oral: Administer tablets and capsules with food or milk to decrease gastric irritation.
    • Do not administer antacids or antidiarrheals within 2 hr of loxapine.

Patient/Family Teaching

  • Instruct patient on need to take loxapine as directed. Take missed doses as soon as remembered, up to 1 hr before next scheduled dose. Patients on long-term high-dose therapy may need to discontinue gradually to avoid withdrawal symptoms (dyskinesia, tremors, dizziness, nausea, and vomiting).
  • Inform patient of possibility of extrapyramidal symptoms and tardive dyskinesia. Instruct patient to report these symptoms immediately to health care professional.
  • Advise patient to change positions slowly to minimize orthostatic hypotension.
  • May cause drowsiness. Caution patient to avoid driving or other activities requiring alertness until response to the medication is known.
  • Caution patient to use sunscreen and protective clothing to prevent photosensitivity reactions.
  • Caution patient to avoid concurrent use of alcohol, other CNS depressants, and OTC medications without consulting health care professional.
  • Instruct patient to use frequent mouth rinses, good oral hygiene, and sugarless gum or candy to minimize dry mouth. Consult health care professional if dry mouth continues for >2 wk.
  • Advise patient to notify health care professional of medication regimen before treatment or surgery.
  • Instruct patient to notify health care professional promptly if sore throat, fever, unusual bleeding or bruising, rash, weakness, tremors, visual disturbances, dark-colored urine, or clay-colored stools occur.
  • Advise patient of need for continued medical follow-up for psychotherapy, eye exams, and laboratory tests, and to detect side effects.

Evaluation/Desired Outcomes

  • Decrease in positive symptoms of schizophrenia (hallucinations, delusions, agitation).
  • Decrease in excitable, manic behavior.

Loxapac

A brand name for LOXAPINE.