Which vitamin's toxicity can lead to symptoms similar to increased intracranial pressure?

Vitamin A toxicity can lead to symptoms resembling increased intracranial pressure, a condition known as pseudotumor cerebri. This is due to the vitamin's role in several biological processes, including the maintenance of epithelial tissues and overall cellular health.

When excessive amounts of Vitamin A are ingested—either through high-dose supplements or dietary sources—it can lead to hypervitaminosis A. This condition can disrupt normal central nervous system function, resulting in symptoms such as headaches, nausea, vomiting, and visual disturbances. The increased intracranial pressure occurs because of the accumulation of cerebrospinal fluid and swelling of the brain, phenomena that can be exacerbated by Vitamin A's effects on the brain.

In contrast, the other vitamins listed do not typically cause increased intracranial pressure as a primary symptom of toxicity. For example, excessive intake of Vitamin C is generally associated with gastrointestinal disturbances, while Vitamin B12 toxicity is rare and usually involves no significant adverse effects. Toxicity from Vitamin D usually results in hypercalcemia rather than increased intracranial pressure. Therefore, the association of Vitamin A toxicity with symptoms similar to increased intracranial pressure is a well-established clinical fact.