Adults: Cardiac Side Effects - Therapeutic doses of Digitek may cause heart block in patients with pre-existing sinoatrial or AV conduction disorders; heart block can be avoided by adjusting the dose of Digitek. Prophylactic use of a cardiac pacemaker may be considered if the risk of heart block is considered unacceptable. High doses of Digitek may produce a variety of rhythm disturbances, such as first-degree, second- degree (Wenckebach), or third-degree heart block (including asystole); atrial tachycardia with block; AV dissociation; accelerated junctional (nodal) rhythm; unifocal or multiform ventricular premature contractions (especially bigeminy or trigeminy); ventricular tachycardia; and ventricular fibrillation. Digitek produces PR prolongation and ST segment depression which should not by themselves be considered Digitek toxicity. Cardiac toxicity can also occur at therapeutic doses in patients who have conditions which may alter their sensitivity to Digitek.
Gastrointestinal Side Effects - Digitek may cause anorexia, nausea, vomiting and diarrhea. Rarely, the use of Digitek has been associated with abdominal pain, intestinal ischemia, and hemorrhagic necrosis of the intestines.
Central Nervous System Side Effects- Digitek can produce visual disturbances (blurred or yellow vision), headache, weakness, dizziness, apathy, confusion and mental disturbances (such as anxiety, depression, delirium, and hallucination).
Infants and Children - The side effects of Digitek in infants and children differ from those seen in adults in several respects. Although Digitek may produce anorexia, nausea, vomiting, diarrhea, and CNS disturbances in young patients, these are rarely the initial symptoms of overdosage. Rather, the earliest and most frequent manifestation of excessive dosing with Digitek in infants and children is the appearance of cardiac arrhythmias, including sinus bradycardia. In children, the use of Digitek may produce any arrhythmia. The most common are conduction disturbances or supraventricular tachyarrhythmias, such as atrial tachycardia (with or without block) and junctional (nodal) tachy-cardia. Ventricular arrhythmias are less common.
Sinus bradycardia may be a sign of impending Digitek intoxication, especially in infants, even in the absence of first-degree heart block. Any arrhythmia or alteration in cardiac conduction that develops in a child taking Digitek should be assumed to be caused by Digitek, until further evaluation proves otherwise.
