A nurse is reviewing the medication history of a client who is in pre-term labor and has a history of peptic ulcer disease.

The nurse should recognize that which of the following medications is contraindicated for this client?

Betamethasone is a corticosteroid that is given to pregnant women who are at risk of preterm delivery to enhance fetal lung maturity and prevent respiratory distress syndrome.It is usually given in two doses, 24 hours apart, and takes effect within 24 hours of administration.

Choice B.Magnesium sulfate is wrong because it is used to prevent seizures in women with severe preeclampsia or eclampsia, not to prevent respiratory distress syndrome.

Choice C.Nifedipine is wrong because it is a calcium channel blocker that is used to inhibit uterine contractions and prolong pregnancy in women with preterm labor, not to prevent respiratory distress syndrome.

Choice D.Indomethacin is wrong because it is a nonsteroidal anti-inflammatory drug that is used to inhibit prostaglandin synthesis and reduce uterine activity in women with preterm labor, not to prevent respiratory distress syndrome.However, it can also cause premature closure of the ductus arteriosus in the fetus and should be avoided after 32 weeks of gestation.

Normal ranges for gestational age are 37 to 42 weeks.

Preterm labor is defined as regular uterine contractions with cervical changes.

This medication will help relax my uterus and stop contractions.

Magnesium sulfate is a tocolytic, a medication used to suppress uterine contractions and delay preterm delivery.The exact mechanism through which magnesium sulfate inhibits contractions is unknown, but researchers believe it likely works by lowering calcium levels in the uterine muscles.

Choice A is wrong because magnesium sulfate is not used to prevent seizures in case of preeclampsia.

Preeclampsia is a condition characterized by high blood pressure and protein in the urine during pregnancy.Magnesium sulfate may be used to treat seizures if they occur with eclampsia, which is a severe complication of preeclampsia.

Choice B is wrong because magnesium sulfate does not help mature the baby’s lungs in case of preterm birth.

Magnesium sulfate may have some neuroprotective effects for the baby, but it does not affect lung development.Steroids are usually given to pregnant women at risk of preterm delivery to help accelerate fetal lung maturation.

Choice D is wrong because magnesium sulfate does not lower blood pressure in case it gets too high.

Magnesium sulfate may have some vasodilatory effects, but it is not used as an antihypertensive agent.Other medications, such as hydralazine or labetalol, are used to treat high blood pressure during pregnancy.