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Nasal decongestant (sympathomimetic)

Pseudoephedrine

Brand names: Sudafed

Pseudoephedrine is an oral sympathomimetic decongestant used for the relief of nasal and sinus congestion associated with colds, allergic rhinitis and sinusitis.

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

Clinical monograph

How it works

It is a sympathomimetic that acts mainly on alpha-adrenoceptors to constrict dilated nasal blood vessels, reducing mucosal swelling and congestion.

Prescribing in practice

  • It is contraindicated with, or within two weeks of, monoamine oxidase inhibitors because of the risk of a hypertensive crisis.
  • Caution is needed in hypertension, ischaemic heart disease, hyperthyroidism and diabetes, and it may cause insomnia and palpitations.
  • Combination with other sympathomimetics increases the risk of cardiovascular adverse effects.

Monitoring

No routine laboratory monitoring is required, but review patients with cardiovascular disease for raised blood pressure or palpitations.

Counselling the patient

  • Taking it later in the day may disturb sleep, so an earlier dose is preferable.
  • Tell us about any heart conditions, high blood pressure, or other medicines you take.
  • Use only for short-term relief of congestion.

Evidence & guidelines

Use reflects established practice for nasal decongestion; the MAOI interaction and cardiovascular cautions are detailed in current prescribing references.

Reference: MHRA guidance on cold medicines; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

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