Symptoms of vitamin a overdose
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Symptoms of Vitamin A Overdose
Acute Hypervitaminosis A Symptoms
Acute hypervitaminosis A occurs when a large dose of vitamin A is ingested in a short period. Symptoms of acute vitamin A toxicity can include nausea, vomiting, headache, dizziness, blurred vision, and loss of muscle coordination. These symptoms are usually reversible once the excessive intake is stopped5.
Chronic Hypervitaminosis A Symptoms
Chronic vitamin A toxicity results from prolonged intake of high doses of vitamin A. This condition can lead to more severe health issues, including:
Hepatic Complications
Chronic vitamin A overdose can cause significant liver damage. Symptoms include hepatocellular damage, portal fibrosis, and even cirrhosis. Patients may present with elevated liver function tests, ascites, and pleural effusion4 6.
Neurologic Complications
Neurologic symptoms are common in chronic vitamin A toxicity. These can include increased intracranial pressure, which may manifest as headaches and visual disturbances. Muscle stiffness, particularly aggravated by exercise, and mental changes such as irritability and confusion are also reported6.
Dermatologic Complications
Skin issues are another hallmark of chronic vitamin A toxicity. Patients may experience dry, rough skin, and hair loss. These dermatologic symptoms are often accompanied by systemic signs of toxicity6.
Respiratory Symptoms
In rare cases, vitamin A toxicity can lead to respiratory issues. For instance, hepatic hydrothorax, a condition where fluid accumulates in the pleural cavity, can occur due to severe liver damage from vitamin A overdose. This condition can cause progressive dyspnea and requires medical intervention4.
Teratogenic Effects
Both excess and deficiency of vitamin A during pregnancy can lead to congenital abnormalities. High doses of vitamin A have been associated with teratogenic effects, primarily affecting the development of the central nervous system in animal studies. Although a direct cause-and-effect relationship in humans has not been firmly established, caution is advised5 6.
Conclusion
Vitamin A overdose, whether acute or chronic, can lead to a range of symptoms affecting various body systems. Acute toxicity is usually reversible with cessation of intake, while chronic toxicity can cause severe and sometimes irreversible damage, particularly to the liver and nervous system. Awareness and careful monitoring of vitamin A intake are crucial to prevent these adverse effects.
Sources and full results
Most relevant research papers on this topic
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