A nursing student administered a biguanide medication to a client with Type 2 diabetes. Which of the following oral diabetes agents is classified as a biguanide?

Rationale:

A. On-off syndrome is a common complication of long-term Levodopa-Carbidopa therapy in Parkinson’s disease. Clients experience sudden, unpredictable fluctuations between periods of good mobility (“on” periods) and severe motor impairment or immobility (“off” periods). This occurs due to pulsatile dopaminergic stimulation and the short half-life of Levodopa, which leads to inconsistent dopamine receptor activation in the basal ganglia. Recognition and management (e.g., adjusting dosing schedules, using controlled-release formulations, or adding adjunct medications) are key to improving functional mobility.

B. Withdrawal syndrome refers to symptoms that occur after abrupt discontinuation of a medication, such as sudden worsening of Parkinsonian symptoms or life-threatening complications with drugs like baclofen. In this case, the client is still taking Levodopa, so this is not a withdrawal effect.

C. Rebound tremor refers to a temporary increase in tremor after a medication wears off or is rapidly discontinued. While related to motor fluctuations, it is not synonymous with the full immobility episodes seen in on-off syndrome. Rebound tremor is a specific component of motor fluctuation, not the broader phenomenon described here.

D. Acute dystonia involves sustained, involuntary muscle contractions causing abnormal postures, often occurring shortly after starting or increasing certain medications (e.g., antipsychotics). The client’s sudden “off” periods of immobility are not dystonic postures but generalized motor blockade, making dystonia an inappropriate description.

Rationale:

A. While the grilled cheese is soft, the apple slices require significant chewing, increasing the risk of choking or aspiration. Patients with Parkinson’s disease often have oropharyngeal dysphagia, making hard, crunchy foods unsafe.

B. Tacos, especially with a shell or tortilla, require complex chewing and strong jaw coordination. Even soft tortillas can be difficult to manage for someone with impaired chewing and swallowing. Refried beans are soft, but the taco itself makes the meal inappropriate.

C. Both scrambled eggs and cottage cheese are soft, high-protein, easy-to-chew and easy-to-swallow foods, making them ideal for patients with dysphagia related to Parkinson’s disease. Soft, moist foods reduce aspiration risk and promote adequate nutrition in patients with impaired chewing, tongue control, and slowed swallowing reflex.

D. Baked chicken is often dry and difficult to chew, and bacon is tough or crispy, both of which significantly increase aspiration risk. These foods require effective mastication, which is impaired in Parkinson’s disease.