codeine/guaifenesin (Robitussin AC)

Indications

expectorant & antitussive

Contraindications

• increased intracranial pressure
• depressed ventilation

Dosage

• 5-10 mL every 4-5 hours PRN; max: 60 mL/day
• 5 mL/dose if 6-12 yo
• 2.5 mL/dose if 2-5 yo

Syrup: guaifenesin 100 mg & codeine phosphate 10 mg/5 mL (120 mL, 240 mL)

Adverse effects

codeine

• common (> 10%)
  • constipation, drowsiness
• less common (1-10%)
  • rash, hives, shortness of breath, troubled breathing, histamine release, decreased urination, blurred vision, dizziness, lightheadedness, dry mouth, false sense of well-being, malaise, headache, hypotension, anorexia, nausea/vomiting, restlessness, burning at site of injection, weakness, ureteral spasm, paradoxical CNS stimulation, confusion, tachycardia, bradycardia
• uncommon (< 1%)
  • convulsions, hallucinations, mental depression, muscle rigidity, paralytic ileus, trembling, biliary spasm, stomach cramps, nightmares, insomnia

guaifenesin

• not common (1-10%)
  • drowsiness, headache, rash, nausea/vomiting, epigastric pain

Drug interactions

• CNS depressants
• phenothiazines
• tricyclic antidepressants (TCA)

More general terms

• Ear nose throat combination

Components

• codeine
• guaifenesin (Robitussin, Fenesin, Humibid LA, Mucinex)