Loxapine Side Effects

Medically reviewed by Drugs.com. Last updated on Oct 27, 2024.

Applies to loxapine: oral capsule.

Other dosage forms:

• inhalation powder

Serious side effects of loxapine

Along with its needed effects, loxapine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking loxapine:

Get emergency help immediately if any of the following symptoms of overdose occur while taking loxapine:

Symptoms of overdose

• dizziness, faintness, or lightheadedness when suddenly getting up from a lying or sitting position
• drowsiness (severe)
• irregular, fast or slow, or shallow breathing
• loss of consciousness
• muscle trembling, jerking, stiffness, or uncontrolled movements (severe)
• pale or blue lips, fingernails, or skin
• troubled breathing (severe)
• unusual tiredness or weakness (severe)

Other side effects of loxapine

Some side effects of loxapine may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Precautions

It is very important that your doctor check your progress at regular visits to make sure this medicine is working properly. Blood tests may be needed to check for unwanted effects.

Do not Stop taking loxapine without first checking with your doctor. Your doctor may want you to gradually reduce the amount you are taking before stopping completely. This will allow your body time to adjust and to keep your condition from becoming worse.

Check with your doctor before using this medicine with alcohol or other medicines that affect the central nervous system (CNS). The use of alcohol or other medicines that affect the CNS with loxapine may worsen the side effects of this medicine, such as dizziness, poor concentration, drowsiness, unusual dreams, and trouble with sleeping. Some examples of medicines that affect the CNS are antihistamines or medicine for allergies or colds, sedatives, tranquilizers, or sleeping medicines, medicine for depression, medicine for anxiety, prescription pain medicine or narcotics, medicine for attention deficit and hyperactivity disorder, medicine for seizures or barbiturates, muscle relaxants, or anesthetics, including some dental anesthetics.

This medicine may cause tardive dyskinesia (a movement disorder). Check with your doctor right away if you have any of the following symptoms while taking this medicine: lip smacking or puckering, puffing of the cheeks, rapid or worm-like movements of the tongue, uncontrolled chewing movements, or uncontrolled movements of the arms and legs.

Check with your doctor right away if you have any of the following symptoms while using this medicine: convulsions (seizures), difficulty with breathing, a fast heartbeat, a high fever, high or low blood pressure, increased sweating, loss of bladder control, severe muscle stiffness, unusually pale skin, or tiredness. These could be symptoms of a serious condition called neuroleptic malignant syndrome (NMS).

This medicine may cause blurred vision, dizziness, drowsiness, trouble with thinking, trouble with controlling body movements, or trouble with your vision, which may lead to falls, fractures or other injuries. Make sure you know how you react to this medicine before you drive, use machines, or do other jobs that require you to be alert, well-coordinated, or able to think or see well.

Dizziness, lightheadedness, or fainting may occur, especially when you get up suddenly from a lying or sitting position. Getting up slowly may help. If the problem continues or gets worse, check with your doctor.

Loxapine can temporarily lower the number of white blood cells in your blood, increasing the chance of getting an infection. If you can, avoid people with infections. Check with your doctor immediately if you think you are getting an infection or if you get a fever, chills, cough or hoarseness, lower back or side pain, or painful or difficult urination.

Check with your doctor immediately if blurred vision, difficulty with reading, or any other change in vision occurs during or after treatment. Your doctor may want your eyes be checked by an ophthalmologist (eye doctor).

Loxapine may cause dry mouth. For temporary relief, use sugarless candy or gum, melt bits of ice in your mouth, or use a saliva substitute. However, if your mouth continues to feel dry for more than 2 weeks, check with your medical doctor or dentist. Continuing dryness of the mouth may increase the chance of dental diseases, including tooth decay, gum disease, and fungus infections.

This medicine may increase prolactin blood levels if used for a long time. Check with your doctor if you have breast swelling or soreness, unusual breast milk production, absent, missed, or irregular menstrual periods, stopping of menstrual bleeding, loss in sexual ability, desire, drive, or performance, decreased interest in sexual intercourse, or an inability to have or keep an erection.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines) and herbal or vitamin supplements.

For healthcare professionals

Applies to loxapine: inhalation powder, intramuscular solution, oral capsule, oral concentrate.

General adverse events

The most common adverse reactions reported with use of the inhaler were dysgeusia, sedation and throat irritation. Drowsiness, extrapyramidal reactions and akathisia have been reported frequently, especially during the first few days of oral therapy.^[Ref]

Gastrointestinal

• Very common (10% or more): Dysgeusia (up to 14%)
• Common (1% to 10%): Dry mouth, throat irritation
• Frequency not reported: Constipation, excessive salivation, paralytic ileus, nausea, tongue protrusion, vomiting^[Ref]

Dysgeusia and throat irritation occurred with inhaled formulations.^[Ref]

Nervous system

• Very common (10% or more): Sedation/somnolence (up to 12%)
• Common (1% to 10%): Dizziness
• Uncommon (0.1% to 1%): Akathisia/restlessness, dystonia, dyskinesia, neck dystonia, tremor
• Frequency not reported: Akinesia, drowsiness, extrapyramidal symptoms, faintness, headache, involuntary muscle contractions, lightheadedness, masked facies, numbness, paresthesia, neuroleptic malignant syndrome, parkinsonian-like symptoms, seizures, shuffling gait, slurred speech, staggering gait, tardive dyskinesia^[Ref]

Sedation occurred in up to 12% of patients who used inhaled formulations.

Drowsiness occurred in patients who used oral formulations.

Drowsiness has been frequently reported at the beginning of therapy or when the dosage is increased. It is generally mild and usually subsides with continued therapy. The incidence of sedation has been reported as less than certain aliphatic phenothiazines, and more than the piperazine phenothiazines.^[Ref]

Other

• Common (1% to 10%): Fatigue, weakness
• Frequency not reported: Hyperpyrexia^[Ref]

Cardiovascular

• Uncommon (0.1% to 1%): Hypotension
• Frequency not reported: Tachycardia, hypertension, orthostatic hypotension, syncope, ECG changes, flushed facies^[Ref]

A few cases of ECG changes similar to those seen with phenothiazines have been reported. It is not known if these were related to loxapine administration.^[Ref]

Psychiatric

• Uncommon (0.1% to 1%): Restlessness
• Frequency not reported: Agitation, confusional state, insomnia, tension^[Ref]

Ocular

• Uncommon (0.1% to 1%): Oculogyration
• Frequency not reported: Blurred vision, dry eyes, ptosis^[Ref]

Respiratory

• Uncommon (0.1% to 1%): Bronchospasm/shortness of breath
• Frequency not reported: Dyspnea, nasal congestion^[Ref]

Bronchospasm occurred with inhaled formulations.

Use of the inhaler was shown to cause bronchospasm in clinical pulmonary safety trials as measured by FEV1 and respiratory signs and symptoms. Additionally, patients with asthma or other pulmonary diseases were shown to be at higher risk and the effect of FEV1 was greater following the second dose (administered 10 hours later).^[Ref]

Endocrine

• Rare (less than 0.1%): Galactorrhea, amenorrhea, gynecomastia, menstrual irregularity^[Ref]

Hematologic

• Rare (less than 0.1%): Leukopenia, neutropenia, agranulocytosis^[Ref]

Hepatic

• Rare (less than 0.1%): Jaundice and/or hepatitis
• Frequency not reported: Hepatocellular injury^[Ref]

Hepatocellular injury described as AST/ALT elevation has been reported in association with loxapine administration; rarely, jaundice and/or hepatitis has been reported as possibly related to treatment.^[Ref]

Dermatologic

• Frequency not reported: Dermatitis, facial edema, pruritus, rash, alopecia, seborrhea^[Ref]

Metabolic

• Frequency not reported: Weight gain, weight loss, polydipsia^[Ref]

Musculoskeletal

• Frequency not reported: Muscle twitching, rigidity^[Ref]

Hypersensitivity

• Frequency not reported: Serious skin reactions^[Ref]

Genitourinary

• Frequency not reported: Urinary retention^[Ref]

See also:

Frequently asked questions

• What drugs cause tardive dyskinesia?

Further information

Loxapine side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer