What are the major effects of magnesium sulfate?

The major effects of magnesium sulfate include its role as a central nervous system depressant, which leads to decreased heart rate, lowered blood pressure, and diminished reflex responses. This medication is commonly utilized in obstetrics, particularly for the management of conditions like preeclampsia and eclampsia.

When administered, magnesium sulfate acts as a muscle relaxant, which can have a calming effect on the heart and blood vessels, ultimately leading to a reduction in blood pressure. Additionally, its depressant qualities can influence the neuromuscular junction, resulting in reduced reflexes, such as diminished tendon reflexes, which are monitored in clinical settings to assess the drug's effects.

In obstetric practice, it’s essential to carefully monitor the patient for these effects to ensure safety, especially because magnesium sulfate can also affect fetal heart rate and uterine contractions. The other choices suggest effects that either do not align with the pharmacodynamics of magnesium sulfate or exaggerate its capabilities, making them less accurate compared to the correct choice.