Diphenhydramine / Phenylephrine Dosage

Medically reviewed by Drugs.com. Last updated on Aug 1, 2023.

Applies to the following strengths: 6.25 mg-2.5 mg/5 mL; 6.25 mg-6.25 mg/5 mL; 12.5 mg-5 mg; 25 mg-7.5 mg/5 mL; 25 mg-10 mg; 12.5 mg-5 mg/15 mL; 12.5 mg-5 mg/5 mL

Usual Adult Dose for Allergic Rhinitis

Diphenhydramine 12.5 mg / phenylephrine 5 mg per 10 mL liquid: 20 mL every 4 hours
Maximum dose: 6 doses per 24 hours

Diphenhydramine 25 mg / phenylephrine 10 mg per tablet: 1 tablet every 4 hours
Maximum dose: 6 doses per 24 hours

Usual Adult Dose for Cold Symptoms

Usual Pediatric Dose for Allergic Rhinitis

Diphenhydramine 6.25 mg / phenylephrine 2.5 mg per 5 mL liquid:
6 to under 12 years: 10 mL every 4 hours
Maximum dose: 6 doses per 24 hours

Diphenhydramine 12.5 mg / phenylephrine 5 mg per 10 mL liquid:
12 years and older: 20 mL every 4 hours
6 to under 12 years: 10 mL every 4 hours
Maximum dose: 6 doses per 24 hours

Diphenhydramine 25 mg / phenylephrine 10 mg per tablet:
12 years and older: 1 tablet every 4 hours
Maximum dose: 6 doses per 24 hours

Usual Pediatric Dose for Cold Symptoms

Renal Dose Adjustments

Data not available

Liver Dose Adjustments

Data not available

Precautions

CONTRAINDICATIONS:

Current use of a monoamine oxidase inhibitor (MAOI) or use within 14 days of stopping a MAOI.
Concomitant use with any other diphenhydramine-containing products, including topical preparations.

Safety and efficacy have not been established in patients younger than 6 years.

Consult WARNINGS section for additional precautions.

Dialysis

Data not available

Other Comments

Administration advice:

Use provided measuring cups for dosing.

Patient advice:

Take only as directed.
Avoid drinking alcohol while on this drug.
Discontinue for nervousness, dizziness, or sleepiness.
Use caution if driving a motor vehicle or operating machinery.
If symptoms last over 7 days or are accompanied by fever, seek medical attention.
If cough lasts over 7 days or comes back, or is accompanied or followed by fever, headache that lasts, or rash, seek medical care promptly.