This nutrient is converted to vitamin A by the body, therefore, deficiency symptoms are the same as those of vitamin A. The earliest symptom is night blindness. Prolonged deficiency leads to more advanced changes in eye tissue. Other potential signs of mild to moderate deficiency include rough, dry skin, loss of appetite, loss of hair luster, brittle nails, joint pain, and possibly increased susceptibility to infection.

Symptoms of deficiency include loss of appetite, nausea, drowsiness, feelings of apprehension, excessive thirst, irrational behavior, fatigue, muscle pain and weakness (usually of the lower limbs); severe cases may lead to irregular heartbeat.

Because of the wide availability of sodium in dietary sources, deficiency is very uncommon. In the rare instances where it does occur, depleted levels have been associated with gas, nausea and vomiting, headache, memory impairment, diminished attention, muscle weakness, heart palpitations, lethargy, and confusion. Extreme cases can cause stupor, seizures, and possibly coma. The development of symptoms depends in large part on the rate of the loss of sodium.

Symptoms of vitamin B₁₂ deficiency are rare because it takes years to develop complications associated with long-term depletion of this nutrient. Irritability, weakness, numbness, anemia, loss of appetite, headache, personality changes, and confusion are some of the signs and symptoms associated with vitamin B₁₂ depletion. Low levels of this vitamin may also be associated with an increased risk of colon cancer, heart disease, brain disorders, and birth defects.

The selected depletions information presented here identifies some of the nutrients that may be depleted by certain medications. The signs and symptoms associated with nutrient deficiency may also indicate conditions other than nutrient deficiency. If you are experiencing any of the signs or symptoms mentioned, it does not necessarily mean that you are nutrient deficient. Nutrient depletion depends upon a number of factors, including your medical history, diet, and lifestyle as well as the length of time you have been taking the medication. Please consult your healthcare provider; he or she can best assess and address your individual healthcare needs, and determine if you are at risk for nutrient depletions from these medications as well as others not listed here.

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