A nurse is reviewing the medication list for a client who has a new diagnosis of type 2 diabetes mellitus. The nurse should recognize which of the following medications can cause glucose intolerance?

Choice A reason: This is incorrect because constipation is not a common or serious adverse effect of antihistamines. However, the patient should increase their fluid and fiber intake and exercise regularly to prevent constipation.

Choice B reason: This is incorrect because abdominal cramps are not a common or serious adverse effect of antihistamines. However, the patient should avoid spicy or fatty foods and take the antihistamine with food or milk to prevent stomach irritation.

Choice C reason: This is correct because drowsiness is one of the most common and bothersome adverse effects of antihistamines. The patient should avoid driving or operating machinery if they experience drowsiness and take the antihistamine at bedtime.

Choice D reason: This is incorrect because decreased libido is not a common or serious adverse effect of antihistamines. However, the patient should inform their provider if they experience any sexual dysfunction or mood changes while taking the antihistamine.

Choice A reason: This is incorrect because orally administered decongestants do not have an immediate onset. They take longer to act than nasal sprays because they have to be absorbed through the gastrointestinal tract. Nasal sprays act directly on the nasal mucosa and have a faster onset.

Choice B reason: This is correct because orally administered decongestants do not cause rebound congestion. Rebound congestion is a condition in which the nasal passages become more swollen and congested after the effect of the nasal spray wears off. This can lead to overuse and dependence on the nasal spray. Orally administered decongestants do not have this effect because they act systemically and not locally.

Choice C reason: This is incorrect because orally administered decongestants do not have a shorter duration. They have a longer duration than nasal sprays because they are metabolized more slowly by the liver. Nasal sprays have a shorter duration because they are eliminated more quickly by the nasal mucosa.

Choice D reason: This is incorrect because orally administered decongestants are not more potent than nasal sprays. They have a similar potency, but they have a different mechanism of action. Orally administered decongestants act on the alpha-adrenergic receptors in the blood vessels, causing vasoconstriction and reducing congestion. Nasal sprays act on the beta-adrenergic receptors in the bronchial smooth muscle, causing bronchodilation and improving airflow.