Differential Diagnosis for 18-year-old Male Feeling Unwell
- Single most likely diagnosis:
- Adderall withdrawal: The patient stopped taking Adderall 3 days ago, which is a common timeframe for withdrawal symptoms to start. Symptoms such as feeling unwell, dilated pupils, vomiting, and headaches are consistent with Adderall withdrawal. The fact that the pupils constricted slightly to light suggests that they are not completely unresponsive, which is more in line with a withdrawal syndrome rather than a more severe neurological condition.
- Other Likely diagnoses:
- Dehydration: Vomiting can lead to dehydration, which may cause or exacerbate symptoms like headaches and feeling unwell. Although dehydration itself might not directly cause dilated pupils, it can contribute to the overall clinical picture.
- Viral illness: The symptoms of vomiting, headache, and feeling unwell could also be indicative of a viral illness. However, the dilated pupils might be less commonly associated with typical viral illnesses unless there's an involvement of the central nervous system.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.):
- Subarachnoid hemorrhage or other intracranial hemorrhages: Although less likely given the context, any severe headache, especially if described as pounding and accompanied by other symptoms like vomiting, necessitates consideration of intracranial hemorrhage. The fact that pupils are dilated but still responsive to light might not fully rule out such conditions, especially in early stages.
- Meningitis: Infection of the meninges can present with headache, vomiting, and altered mental status. While the presence of dilated pupils that constrict to light might be less typical, meningitis is a condition that requires prompt diagnosis and treatment.
- Rare diagnoses:
- Serotonin syndrome: Although the patient stopped Adderall, if he had recently taken any other medications that could increase serotonin levels, serotonin syndrome could be considered. However, this would typically present with more pronounced autonomic instability and neuromuscular abnormalities.
- Adrenergic crisis: This could be considered if the patient had taken or been exposed to certain substances that cause a massive adrenergic surge, but the clinical context provided does not strongly support this diagnosis.