Child is suspected to have consumed some substance, presents with tachycardia, bronchodilation, elevated temperature and constipation. The substance ingested is most probably ?
**Core Concept**
The child's symptoms suggest exposure to a substance that causes sympathomimetic effects, such as tachycardia and bronchodilation, while also having anticholinergic properties, leading to constipation and elevated temperature.
**Why the Correct Answer is Right**
The combination of symptoms is indicative of exposure to a substance that activates the sympathetic nervous system, causing the release of catecholamines, which in turn stimulates beta-2 receptors in the bronchi, leading to bronchodilation. The anticholinergic effects of the substance inhibit the parasympathetic nervous system, resulting in constipation and elevated temperature. The substance also causes an increase in heart rate due to the stimulation of beta-1 receptors in the heart.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as it does not explain the combination of sympathomimetic and anticholinergic effects observed in the child.
**Option B:** This option is incorrect as it does not account for the anticholinergic effects, such as constipation, observed in the child.
**Option C:** This option is incorrect as it does not explain the sympathomimetic effects, such as tachycardia and bronchodilation, observed in the child.
**Clinical Pearl / High-Yield Fact**
Substances with sympathomimetic and anticholinergic effects, such as antihistamines, tricyclic antidepressants, and certain plant alkaloids, can cause a range of systemic effects, including cardiovascular, respiratory, and gastrointestinal symptoms.
**Correct Answer:** D.