acetaminophen/diphenhydramine/dextromethorphan (Diabetic Tussin Nighttime Cold and Flu)

Dosing and uses of Diabetic Tussin Nighttime Cold and Flu (acetaminophen/diphenhydramine/dextromethorphan)

• Adult
• Pediatric

 

Adult dosage forms and strengths

acetaminophen/diphenhydramine/dextromethorphan

oral solution

• (325mg/12.5mg/10mg)/5mL

 

Cold & Flu

Indicated for relief of cold and flu symptoms

10 mL PO q4hr PRN; not to exceed 6 doses/24 hr

 

Pediatric dosage forms and strengths

acetaminophen/diphenhydramine/dextromethorphan

oral solution

• (325mg/12.5mg/10mg)/5mL

 

Cold & Flu

Indicated for relief of cold and flu symptoms

<6 years: Safety and efficacy not established

6-12 years: 5 mL PO q4hr PRN; not to exceed 6 doses/24 hr

>12 years: As adults; 10 mL PO q4hr PRN; not to exceed 6 doses/24 hr

 

Diabetic Tussin Nighttime Cold and Flu (acetaminophen/diphenhydramine/dextromethorphan) adverse (side) effects

Frequency not defined

Common

• Nausea/Vomiting
• Thick sputum
• Constipation
• Drowsiness
• Dizziness
• Sedation
• Blurred vision
• Nystagmus

Less Common

• Angioedema, Laryngeal edema
• Disorientation, Dizziness, Sedation, Confusion, Decreased cognitive function in elderly
• Pruritic maculopapular rash, Rash, Stevens-Johnson syndrome, Toxic epidermal necrolysis, Urticaria
• Agranulocytosis, Leukopenia, Neutropenia, Pancytopenia, Thrombocytopenia
• Thrombocytopenic purpura
• Hepatotoxicity, Liver failure Gastrointestinal hemorrhage, Nephrotoxicity, Pneumonitis, Anaphylactoid reactions
• Anticholinergic effects, Xerostomia, Dry nasal mucosa, Pharyngeal dryness

 

Warnings

Contraindications

Hypersensitivity

Hepatitis or hepatic/renal dysfunction, alcoholism

Repeated administration in patients with anemia or cardiac, pulmonary, or renal disease

Use within 14 days of MAO inhibitor therapy

Lower respiratory disease, eg, asthma (controversial)

Premature newborns and neonates

Nursing women

 

Cautions

Acetaminophen is found in many other dosage forms and products, check label carefully to avoid overdose

Acetaminophen: Risk for rare, but serious skin reactions that can be fatal; these reactions include Stevens-Johnson Syndrome (SJS), toxic epidermal necrolysis (TEN), and acute generalized exanthematous pustulosis (AGEP); symptoms may include skin redness, blisters and rash

Risk of hepatotoxicity is higher in alcoholics or with use of more than one acetaminophen-containing product

G6PD deficiency

Phenylketonuria (phenylalanine in orange flavoring)

Driving or operating machinery

Avoid alcohoL

Caution in narrow angle glaucoma, prostatic hypertrophy, stenosing peptic ulcer, pyloroduodenal obstruction, or bladder neck obstruction

 

Pregnancy and lactation

 

Pregnancy category

Acetaminophen: Class B

Diphenhydramine: Class B

Dextromethorphan: Class C

 

Lactation

Acetaminophen: Excreted in breast milk; compatible with breastfeeding

Diphenhydramine: Enters breast milk/contraindicated

Dextromethorphan: Unknown if excreted in breast milk, use caution

 

Pregnancy categories

A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.

B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.

C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.

X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.

NA: Information not available.

 

Pharmacology of Diabetic Tussin Nighttime Cold and Flu (acetaminophen/diphenhydramine/dextromethorphan)

Mechanism of action

Acetaminophen blocks pain impulse generation peripherally and may inhibit the generation of prostaglandin in the CNS; reduces fever by inhibiting the hypothalamic heat-regulating center

Diphenhydramine: competitively blocks histamine from binding to H1 receptors; significant antimuscarinic activity and penetrates CNS, which causes pronounced tendency to induce sedation

Dextromethorphan is a cough suppressant that acts centrally on the cough center in the medulla

 

Pharmacokinetics

Acetaminophen

• Peak plasma time: 10-60 min (PO immediate release); 60-120 min (PO extended release); 6 hr (PO 500 mg tablet); 8 hr (PO 650 mg extended release tablet)
• Vd: 1 L/kg
• Protein binding: 10-25%
• Metabolism: Liver (microsomal enzyme systems); conjugation (glucuronic acid)
• Half-life: 1.25-3hr
• Excretion: Urine

Diphenhydramine

• Bioavailability: 42-62% (PO)
• Onset: 15-30 min
• Duration: 4-6 hr
• Peak plasma time: 2 hr (PO)
• Protein bound: 98.5%
• Vd: 22 L/kg (children); 17 L/kg (adults); 14 L/kg (Elderly)
• Half-life: 5 hr (children); 9 hr (adults); 13.5 hr (elderly)
• Excretion: Urine (50-75%)

Dextromethorphan

• Onset: 15-30 min
• Duration: 3-6 hr
• Metabolism: Hepatic P450 enzyme CYP2D6
• Excretion: Urine
• Half-life: 2-4 hr (extensive metabolizers); 24 hr (poor metabolizers)
• Peak plasma time: 2-3 hr