Risperidone (Risperdal®) and aripiprazole (Abilify®) are used because they can often make a tremendous difference for the patient’s quality of life. These atypical neuroleptic drugs decrease anxiety, obsessive-compulsive behaviour, aggressive behaviour, rages, tics, as well as emotional and/or behavioural reactivity. They improve self-control and calm thinking and feeling, allowing the patient to function better.
Risperidone has possible metabolic effects that are much less frequently observed with aripiprazole. These possible metabolic effects include increased appetite and weight gain. It is important to avoid weight gain as it is difficult to lose weight after it has been gained. Significant weight gain can increase the risk for diabetes, hyper-cholesterolemia, and heart disease. Risperidone can increase the risk for diabetes independent of weight gain. Risperidone can increase prolactin that in turn can lead to breast enlargement.
Other very rare side effects of both risperidone and aripiprazole include:
1) Both may interfere with temperature regulation. It is important to make sure children do not get over-heated when exercising or participating in sports activities in the warmer seasons. Lots of fluids, sun protection, and avoidance of strenuous exercise in very warm, hot, and humid weather are helpful in this regard.
2) Neuroleptic malignant syndrome (NMS) is a condition characterized by children being highly febrile, rigid, obviously very ill, and often confused. In such cases, children may have to be admitted to ICU for treatment. This complication is extremely rare but potentially life threatening.
3) Acute oculogyric crisis is not life threatening and consists of a spasm of neck and eye muscles resulting in the bending backwards of the head with the eyes rolling upwards. This complication responds quickly to treatment in the emergency room (Benadryl®, Cogentin®) and is very rare.
4) Tardive dyskinesia is a condition in which the patient develops difficulties with smooth movements of skeletal muscles. This condition is not unlike patients with Parkinson’s. Stuttering can occur. This complication is also very rare.
Before starting risperidone (Risperdal®) or aripiprazole (Abilify®), an ECG (electro-cardiogram) is ordered as a precaution to document that the electrical conductivity in the heart is normal. In very rare instances these medications can change the QT interval. (The QT interval is the period of time during which the ventricles of the heart depolarize and re-polarize.) Patients with congenital Long QT Syndrome have to be monitored very carefully. This condition may be detected only by performing an ECG.
It is occasionally necessary to arrange for blood work to check on prolactin, lipid profile, thyroid function, and liver functions.
As a general rule, we use these medications as little as possible, and for as short a period of time as possible.
It must also be noted that, although risperidone and aripiprazole are approved for use in adults, these medications are used “off label” in patients younger than 18 years of age: while there is a significant and increasing body of scientific literature regarding their use in patients under the age of 18 years, these medications are not formally approved by the FDA or by Health Canada. Therefore pharmaceutical companies are not allowed to advertise the use of these medications in patients under the age of 18 years.