Drug General Information (ID: DDIOV8273G)
Drug Name			Vitamin A		Drug Info		Isotretinoin		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Vitamins				Antiacne Agents/Antineoplastics
Structure

Mechanism of Vitamin A-Isotretinoin Interaction (Severity Level: Major)
Increased risk of pseudotumor cerebri Click to Show/Hide Mechanism Graph
Drug Name		Vitamin A				Isotretinoin
Mechanism		Pseudotumor cerebri				Pseudotumor cerebri
Key Mechanism Factor 1
		Factor Name		Pseudotumor cerebri
		Factor Description		Pseudotumor cerebri syndrome is an elevated intracranial pressure associated with papilledema without an established cause of intracranial hypertension. Symptoms include post-ocular headache, tinnitus, blurred vision, diplopia, transient blindness, nausea and vomiting, dizziness, and swelling of the optic disc in the eye.
Mechanism Description		Increased risk of pseudotumor cerebri by the combination of Vitamin A and Isotretinoin

Recommended Action
Management		Patients receiving retinoid therapy should avoid concurrent use of other retinoids or vitamin A supplements in excess of the recommended daily allowance. Patients should be made aware of vitamin A sources in vitamin supplements, fortified foods and over-the-counter medications, and be advised to contact their physician if they experience signs of hypervitaminosis A such as inflammation or bleeding of the gums or lips dry, scaly skin alopecia pruritus erythema headache vertigo and nausea. Patients should discontinue the medication and seek immediate medical attention if they develop signs and symptoms of pseudotumour cerebri or hepatotoxicity.

References
1	Cerner Multum, Inc. "UK Summary of Product Characteristics.".
2	Product Information. Accutane (isotretinoin). Roche Laboratories, Nutley, NJ.
3	Product Information. Vesanoid (tretinoin). Roche Laboratories, Nutley, NJ.
4	Cerner Multum, Inc. "Australian Product Information.".
5	Product Information. Soriatane (acitretin). Roche Laboratories, Nutley, NJ.