Question 1

How do decongestants relieve nasal congestion?

Accepted Answer

Decongestants activate α-adrenergic receptors, constricting small blood vessels in nasal membranes. This vasoconstriction opens clogged nasal passages and facilitates sinus drainage, relieving congestion caused by allergies, colds, sinusitis, and upper respiratory infections. The mechanism works by mimicking sympathetic nervous system stimulation.

Question 2

What are the two main types of decongestants?

Accepted Answer

Decongestants are classified as β-phenylethylamine derivatives or imidazoline derivatives. β-phenylethylamine derivatives like epinephrine, phenylephrine, and pseudoephedrine act on α1-adrenoreceptors. Imidazoline derivatives such as oxymetazoline, naphazoline, tetrahydrozoline, and xylometazoline act on α2-adrenoreceptors, both producing vasoconstriction.

Question 3

Why should topical decongestants be limited to three days?

Accepted Answer

Topical decongestants should not be used for more than three consecutive days to avoid rebound nasal congestion, a phenomenon where congestion returns or worsens after discontinuing the medication. While they provide short-term relief, prolonged use can lead to dependency and worsen symptoms upon cessation.

Question 4

What side effects do topical decongestants cause?

Accepted Answer

Topical decongestants may occasionally cause nasal burning, stinging, and dryness, though these effects are typically mild and temporary. These local side effects are generally less concerning than systemic effects, making topical formulations a safer option for short-term use in most patients.

Question 5

How do oral decongestants differ from topical forms?

Accepted Answer

Oral decongestants provide longer-lasting relief than topical forms but are systemically absorbed, causing potential systemic side effects. These include nervousness, tachycardia, blurred vision, vomiting, and insomnia. Patients with cardiovascular disease and uncontrolled hypertension require careful monitoring due to cardiovascular stimulation risks.

Question 6

What forms are decongestants available in?

Accepted Answer

Most decongestants are available over the counter in multiple forms including nasal sprays, nasal drops, and oral tablets. Topical formulations deliver medication directly to nasal passages for rapid local relief, while oral forms provide systemic distribution for longer-lasting effects across the upper respiratory tract.

Question 7

Which patients require special consideration when using oral decongestants?

Accepted Answer

Patients with cardiovascular disease and uncontrolled hypertension require special consideration when using oral decongestants because these agents cause cardiovascular stimulation. Healthcare providers should discuss systemic side effects like nervousness, tachycardia, and insomnia with these patients before recommending oral decongestant therapy.

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