Final answer:
Nifedipine is associated with more adverse effects than magnesium sulfate or terbutaline. It is a calcium channel blocker that causes side effects by dilating blood vessels and decreasing heart contraction strength.
Step-by-step explanation:
The drug that is associated with more adverse effects than magnesium sulfate or terbutaline is nifedipine. Nifedipine, along with other calcium channel blockers such as amlodipine, felodipine, nimodipine, and verapamil, can cause a range of side effects due to their mechanism of action which involves dilating blood vessels by blocking calcium channels in the heart and blood vessel walls. They are known as negative inotropic agents because they can decrease the strength of the heart's contraction and stroke volume (SV).