Vitamin A Toxicity/Retinol Toxicity

WHAT IS IT?

Vitamin A (retinol) toxicity is exactly as it sounds: a condition caused by excessive amounts of vitamin A in the body.

WHAT CAUSES IT?

Typically this condition is caused by the excessive ingestion of vitamin A in the body (such as by taking too many vitamin supplements). Vitamin A can be found in:

  • Butter
  • Yellow vegetables
  • Egg yolks

Similarly long term usage of retinoid medications (derived from vitamin A) may also be the cause of this condition.

WHY IS IT A PROBLEM?

High levels of vitamin A will accumulate in the liver over time

WHAT MAKES US SUSPECT IT?

Risk factors

High dose vitamin supplementation, usage of vitamin A derived medications (retinoids)

Initial Presentation

Acute toxicity is characterized by:

  • Nausea
  • Vomiting
  • Vertigo
  • Blurred vision

Chronic toxicity is characterized by: 

Physical Exam Findings

Vital signs: hypertension may be present in patients with pseudotumor cerebri

Abdominal exam can reveal an enlarged liver

HOW DO WE CONFIRM A DIAGNOSIS?

Serum test of vitamin A can show increased levels within the blood that with a history of excessive Vitamin A intake, can help make the diagnosis.

HOW DO WE TREAT IT? 

Stop the intake of vitamin A:

  • Discontinue retinoid medications
  • Halt dietary intake of vitamin A
HOW WELL DO THE PATIENTS DO?

Patients generally recover well after the intake of vitamin A is halted.

WAS THERE A WAY TO PREVENT IT? 

Avoiding excessive intake of vitamin A will prevent this toxicity from occurring.

WHAT ELSE ARE WE WORRIED ABOUT?

Excessive vitamin A during pregnancy can cause various problems including:

  • Spontaneous abortion
  • Birth defects such as cleft palate and cardiac abnormalities.

Hypercalcemia can be caused by excessive vitamin A intake

OTHER HY FACTS?

Vitamin A is one of the fat soluble vitamins.

ARCHIVE OF STANDARDIZED EXAM QUESTIONS 

This archive compiles standardized exam questions that relate to this topic.

Page Updated: 07.24.2016