Generic Name

Sudafed

Mechanism

Sudafed (pseudoephedrine) is a sympathomimetic alkaloid that functions primarily as a selective α₁‑adrenergic receptor agonist.
• Vasoconstriction: Stimulates α₁ receptors in the mucosal blood vessels → reduced mucosal edema and congestion.
• Neurotransmitter release: Modest stimulation of peripheral norepinephrine release, contributing to systemic pressor effects.
• Minimal β‑adrenergic activity → minimal bronchodilation, making it unsuitable for asthma therapy.

The drug lacks direct anti‑inflammatory or anti‑infection effects; it is purely a vasoconstrictor.

Pharmacokinetics

Indications

• Nasal congestion from *acute viral rhinosinusitis*, *allergic rhinitis*, or *common cold*
• Post‑operative congestion or after sinus surgery
• Mild to moderate management of nasal obstruction in *non‑phlegmatic sinusitis*

Not indicated for asthma, chronic obstructive pulmonary disease, or systemic infections.

Contraindications

• Severe arterial hypertension or uncontrolled cardiovascular disease
• Pheochromocytoma (risk of hypertensive crisis)
• Hypersensitivity to pseudoephedrine or structurally related alkaloids
• Use with monoamine oxidase inhibitors (MAOIs) – concurrent use contraindicated
• Pregnancy: Category C; consider phenylephrine or other non‑contraceptive options if necessary
• Breastfeeding: Limited data – use only if clearly needed
• Hypertensive emergency: Contraindicated

Warnings
• Potential for increased blood pressure, tachycardia, insomnia, anxiety
• Phototoxicity: not significant but caution in patients on other photosensitizing drugs
• Masking of urinary tract obstruction: may cause nocturia; monitor in at risk populations

Dosing

• Initial titration: start at 60 mg q12 h, increase to 60 mg q8 h only if necessary.
• Stop abruptly in case of severe hypertension or tachycardia.

Adverse Effects

Common (≥10 %)
• Headache, dizziness, insomnia, nervousness
• Dry mouth, nausea, mild gastrointestinal upset
• Tachycardia, mild hypertension

Serious (≤1 %)
• Severe hypertension (sudden rise > 30 mmHg)
• Torsades de pointes (rare with concomitant QT‑prolonging agents)
• Neuropsychiatric events (agitation, hallucinations, seizures) – more likely in high doses or overdose
• Vision changes (pupil dilation, blurred vision)

Monitoring

• Blood pressure & heart rate: baseline, 2 h after first dose, then q8–12 h if hypertensive.
• Pregnancy test if used in women of childbearing age.
• Renal function: serum creatinine & eGFR if >60 y or chronic kidney disease.
• Drug interactions: Review concurrent MAOIs, SSRIs, or sympathomimetics.
• Pregnancy category & pediatric advisories: document consent and age compliance.

Clinical Pearls

• Switch from phenylephrine: Pseudoephedrine has superior systemic efficacy; phenylephrine’s bioavailability is 20 cigarettes/day**: Smoking increases clearance, necessitating higher or more frequent dosing for equivalent effect.
• Pregnancy Guidance: If a female patient is pregnant, consider a phenylephrine nasal spray (not oral) or a short‑term oral antihistamine plus saline irrigation.
• Add‑on therapy: Combining Sudafed with an antihistamine (e.g., cetirizine) can address both congestion and pruritus but monitor cumulative CNS side effects.
• Use of the extended‑release form: Only in patients for whom twice‑daily dosing is impractical; avoid mixed dosing schedules to prevent peak‑trough variability.
• Quantity control: U.S. regulation limits the amount per sale; pharmacists should verify patient history to mitigate misuse.

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• References

1. Katzung BG, Trevor AJ. *Basic & Clinical Pharmacology*. 14th ed. 2022.

2. FDA Label: *Sudafed* (Pseudoephedrine Hydrochloride). Updated 2023.

3. European Drugs Agency. *Pseudoephedrine – Pharmacology & Clinical Use*. 2021.