What is a common effect of a TCA overdose?

A common effect of a tricyclic antidepressant (TCA) overdose is tachycardia, which is an elevated heart rate. This occurs due to the anticholinergic effects of TCAs, which block the action of acetylcholine in the body. As a result, the heart rate increases, and this effect can lead to significant cardiovascular complications in overdose situations.

Tachycardia is particularly problematic in the context of TCA toxicity, as it can contribute to arrhythmias and other serious heart issues. Recognizing this symptom is crucial for the management of TCA overdose, as it helps guide appropriate treatment protocols to stabilize the patient's condition.

In contrast, the other options, while they may be associated with certain medical conditions, do not represent the classic symptoms of TCA overdose. For instance, bradycardia, which is a slower than normal heart rate, is generally not expected in TCA toxicity due to its stimulant effects on the heart. Hypoglycemia and weight loss are also not common presentations of TCA overdose, as these are more related to different metabolic or psychiatric issues rather than the direct effects of the drug itself.