What are common signs of magnesium sulfate toxicity?

Magnesium sulfate toxicity can present with specific clinical signs that reflect impaired neuromuscular function and central nervous system effects. One of the hallmark indicators of toxicity is the absence of deep tendon reflexes, which occurs as magnesium levels rise excessively. This is due to magnesium's role as a neuromuscular blocker; when serum magnesium levels are too high, neuromuscular transmission can become impaired, leading to diminished or absent reflex responses.

Blurred vision can also occur, as increased magnesium levels can affect the central nervous system, causing visual disturbances. This combination of absent deep tendon reflexes and blurred vision is a significant sign of magnesium toxicity and warrants immediate attention, including potential discontinuation of magnesium sulfate administration and further evaluation of the patient's magnesium levels.

Recognizing these specific signs is crucial for healthcare providers to manage patients receiving magnesium sulfate, particularly in settings like obstetrics, where it is often administered for conditions such as preeclampsia or eclampsia. In contrast, the other options listed do not directly relate to magnesium sulfate toxicity and reflect different physiological responses or conditions.