Guaifenesin

Guaifenesin

Drug monograph · NCLEX study reference
Trade names	Mucinex
Therapeutic class	Expectorant
Pharmacologic class	Expectorant
Onset / peak / duration	ER lasts about 12 hours.
Half-life / level	About 1 hour; no routine level.
Routes	PO (oral)
High-alert (ISMP)	No
Black box warning	None
Antidote / reversal	Not applicable.
Pregnancy / lactation	Use if needed.

Nursing pharmacology study reference (NCLEX-style monograph). Numeric values are standard teaching ranges for study and must be verified against current manufacturer labeling before clinical use. This is educational content, not prescribing guidance.

Guaifenesin (brand name Mucinex) — Expectorant; Expectorant.

Identification

• Therapeutic class: Expectorant.
• Pharmacologic class: Expectorant.

Pharmacology

• Mechanism of action: Thins and loosens respiratory secretions to ease productive cough.
• Onset / peak / duration: ER lasts about 12 hours.
• Half-life / therapeutic level: About 1 hour; no routine level.

Clinical use

• Indications: Productive cough, chest congestion.
• Usual dose, route, frequency: 200 to 400 mg PO every 4 hours, or ER 600 to 1,200 mg every 12 hours.
• Maximum dose / adjustments: Max about 2,400 mg/day.

Safety

• Contraindications: Hypersensitivity.
• Black box warning: None.
• Interactions: Minimal.
• Pregnancy / lactation: Use if needed.
• High-alert: No.

Adverse effects

• Common side effects: Nausea, dizziness, headache.
• Serious effects to report: Rash, persistent cough beyond a week.
• Antidote / reversal: Not applicable.

Nursing process

• Assessment before administration: Cough type, hydration.
• Interventions during therapy: Encourage fluids to aid effect.
• Monitor: Cough and secretions.
• Evaluation / expected outcome: Easier clearing of secretions.

Patient teaching

• Patient teaching: Drink plenty of water; swallow ER whole.
• Notify provider if: Cough lasts more than 7 days or comes with high fever.
• Administration tips: With water; ER not crushed.