What symptom is least likely to be seen in a patient who has ingested Taro?

Severe lethargy is the symptom that is least likely to be seen in a patient who has ingested Taro. Taro contains calcium oxalate crystals, which can cause irritation and inflammation in the mouth and gastrointestinal tract. The immediate reactions typically involve hypersalivation due to oral irritation and swelling of the lips and tongue, as well as gastrointestinal distress that can lead to vomiting.

While lethargy can occur in severe cases of toxicity or dehydration, it is not the primary or immediate response that is associated with the ingestion of Taro. Instead, hypersalivation, swelling, and vomiting are more direct reactions to the irritant properties of the ingested plant material. Thus, severe lethargy, as an indirect or secondary effect, is less likely to be present compared to these other symptoms when Taro is ingested. This makes it the least probable symptom in this context.