**Question:** Which of the following is NOT a feature of thyrotoxicosis?

A. Increased heart rate
B. Weight loss
C. Increased appetite
D. Dry skin

**Core Concept:** Thyrotoxicosis is a condition characterized by excessive thyroid hormone production, leading to various clinical manifestations. These manifestations include increased heart rate (tachycardia), weight loss (despite increased caloric intake), increased appetite, and dry skin.

**Why the Correct Answer is Right:** Dry skin is not specifically mentioned as a feature of thyrotoxicosis. While hyperthyroidism can result in skin changes, dry skin is not a universal finding and may not be prominent in all cases of thyrotoxicosis.

**Why Each Wrong Option is Incorrect:**

A. Increased heart rate (tachycardia): This is a common feature of thyrotoxicosis, as excess thyroid hormone leads to increased cardiac demand and decreased vagal tone, resulting in tachycardia.

B. Weight loss: In some cases, weight loss may be present due to increased caloric expenditure in hyperthyroidism.

C. Increased appetite: Thyrotoxicosis can lead to increased food intake and weight loss, rather than increased appetite.

D. Dry skin: As mentioned earlier, dry skin is not a universal feature and may not be prominent in all cases of thyrotoxicosis.

**Clinical Pearl:** When assessing a patient with suspected thyrotoxicosis, a thorough examination should be performed to identify other common features such as goiter, warm/tender skin, and easy fatigability. However, the presence of dry skin does not rule out thyrotoxicosis, as it is not a universal finding.

**Correct Answer:** **D. Dry skin**

**Why D is Incorrect:** As mentioned, dry skin is not a universal feature of thyrotoxicosis and can be present in some cases but not others. While other features like increased heart rate, weight loss, and increased appetite are more commonly associated with this condition.