Anticholinergic Toxicity: This condition is characterized by dilated pupils, tachycardia, hypotension, and confusion due to the blockade of acetylcholine receptors in the central and peripheral nervous system. It can be caused by various medications, plants, or substances.

Sympathomimetic Toxicity: Caused by substances like cocaine, amphetamines, or certain medications, leading to increased sympathetic activity, which can present with dilated pupils, tachycardia, hypertension (though hypotension can occur in severe cases due to cardiovascular collapse), and confusion.
Severe Dehydration or Hypovolemia: Can cause hypotension, tachycardia, and confusion. While dilated pupils might not be a direct effect, severe dehydration can lead to a state where pupils become dilated due to decreased intracranial pressure or as a response to stress.
Sepsis: Especially in its early stages, sepsis can present with hypotension, tachycardia, and confusion. Dilated pupils might be seen as part of the systemic inflammatory response syndrome (SIRS) or due to the direct effect of the causative pathogen on the central nervous system.

Anaphylaxis: Although typically associated with urticaria, angioedema, and bronchospasm, anaphylaxis can also present with hypotension, tachycardia, and confusion. Dilated pupils might not be a primary symptom but can occur due to the systemic nature of the reaction.
Intracranial Hemorrhage: Can cause sudden confusion, and depending on the location and size of the hemorrhage, might lead to pupillary dilation (especially if it affects the third cranial nerve), hypotension, and tachycardia due to increased intracranial pressure or brainstem involvement.
Myocardial Infarction: Especially if it involves the right ventricle or leads to cardiogenic shock, can present with hypotension and tachycardia. Confusion might occur due to decreased perfusion of the brain, and dilated pupils could be seen in the context of shock or as a pre-terminal sign.

Pheochromocytoma: A rare tumor of the adrenal gland that can cause episodic or sustained hypertension, tachycardia, and other symptoms due to excessive catecholamine release. While hypotension is less common, it can occur, especially if there's significant volume depletion or during certain phases of the disease.
Neuroleptic Malignant Syndrome (NMS): A life-threatening neurological disorder most often caused by an adverse reaction to neuroleptic or antipsychotic medication. It can present with fever, confusion, altered mental status, and autonomic dysfunction, which might include hypotension, tachycardia, and changes in pupil size.
Status Epilepticus: Prolonged or recurrent seizures without full recovery between them. It can lead to confusion, altered mental status, and autonomic instability, including changes in blood pressure, heart rate, and potentially pupil size, especially if there's significant sympathetic nervous system activation.