Adverse events after the administration of haloperidol decanoate are the same, which can occur with the use of other dosage forms of haloperidol.
Extrapyramidal symptoms:
With long-term use, there may be tremors, rigidity of muscles, bradykinesia, akathisia, acute muscular dystonia, oculogic crisis, laryngeal dystonia (spastic dysphonia).
Correction:it is necessary to prescribe antiparkinsonian preparations of m-cholinoblocking action. However, it must be borne in mind that their constant use reduces the effectiveness of haloperidol.
Late dyskinesia:
As with other antipsychotics, it can occur with prolonged use or withdrawal of the drug. It is manifested by rhythmic movements of muscles of the face, lips, tongue or jaw area that can not be controlled by volitional control. This disorder in some patients may have the nature of residual events. Disorders cease with the resumption of haloperidol, with increasing doses or when switching to treatment with another drug. When signs of late dyskinesia, it is advisable to continue treatment with another drug.
Malignant neuroleptic syndrome (CNS):
The use of haloperidol can cause CNS. A rare reaction that arises in the idiosyncrasy type is characterized by hyperthermia, generalized rigidity of the muscles, vegetative lability, shortness of breath or rapid breathing, arrhythmias, increased or decreased blood pressure (BP), increased sweating, urinary incontinence, epileptic seizures, and impaired consciousness. The early sign of the NSA is often hyperthermia. When symptoms of NSA appear in all cases, it is necessary to interrupt treatment with antipsychotic drugs and, under conditions of careful observation, to start supporting, including detoxification, therapy.
Other side effects from the central nervous system (CNS):
Depression, inhibition (up to a state similar to lethargy), or psychomotor agitation, insomnia or drowsiness (especially at the beginning of treatment), headache, transient mnestic-intellectual disorders, dizziness, motor anxiety, anxiety, fear, or euphoria, epileptic seizures type "grand mal" and the resumption of psychotic symptoms (the development of a paradoxical reaction).
Digestive system:
When used in high doses - decreased appetite, dry mouth, hypo-salivation, nausea, vomiting, diarrhea or constipation, impaired liver function, until the development of jaundice.
Endocrine system:
Because of the antidopaminic effect, hyperprolactinaemia, galactorrhea, gynecomastia, oligo- and amenorrhea, hyper- or hypoglycemia, a decrease in the secretion of antidiuretic hormone can be observed.
The cardiovascular system:
When used in high doses - reduced blood pressure, orthostatic hypotension, arrhythmias, tachycardia, changes in the electrocardiogram (ECG) (prolongation of the QT interval)
On the part of the organs of hematopoiesis:
Transient "leukopenia or leukocytosis, agranulocytosis, erythropenia and a tendency to monocytosis.
Allergic reactions:
In particular, the phenomena of urticaria, anaphylaxis, photosensitization, maculopapular and acneiform changes in the skin, bronchospasm, laryngospasm, hyperpyrexia.
From the genitourinary system:
Urinary retention (with prostatic hyperplasia), peripheral edema, decreased potency, increased libido, priapism.
Laboratory indicators:
Hyponatremia.
Other side effects:
Alopecia, heat stroke, weight gain, local reactions, cataract, retinopathy, blurred vision.
Elderly patients may experience seizures of angle-closure glaucoma.