EXYLIN SYRUP 100ML

Indications

Approved Uses

Temporary relief of allergy and common-cold symptoms mediated by histamine (e.g., sneezing, rhinorrhea, itchy/watery eyes, itching of nose/throat); may also be used for urticaria/pruritus due to allergic causes.

Off-Label Uses

Insomnia (short-term), motion sickness, and nausea/vomiting (antiemetic) are common off-label uses; other uses (e.g., parkinsonian tremor) are less common and should be clinician-directed.

Dosage & Administration

Dosing by Condition

Allergic symptoms (adults/≥12 years): 25-50 mg every 4-6 hours as needed (max 300 mg/day). Children 6-11 years: 12.5-25 mg every 4-6 hours (max 150 mg/day). Children 2-5 years: 6.25 mg every 4-6 hours (max 37.5 mg/day).

Initial Dose

25mg (approximately 9ml syrup) every 4-6 hours in adults

Maintenance Dose

25-50 mg every 4-6 hours as needed.

Children's Dosage

Children 6-12 years: 12.5-25mg (4.5-9ml) every 4-6 hours, max 150mg/day. Children 2-6 years: 6.25mg (approximately 2.2ml) every 4-6 hours, max 37.5mg/day. Not recommended under 2 years.

Dose Adjustment Notes

Elderly: use lower doses/avoid when possible due to increased anticholinergic and sedative adverse effects (Beers criteria); hepatic impairment: use caution as metabolism is hepatic.

How to Take

Shake well before each dose; measure using a calibrated measuring device (oral syringe or dosing cup/spoon); may be taken with or without food (take with food/milk if GI upset occurs).

Side Effects

Common Side Effects

Drowsiness/sedation, dizziness, impaired coordination, dry mouth/nose/throat, blurred vision, constipation, urinary retention, nausea; may thicken bronchial secretions.

Side Effect Frequency

Sedation/drowsiness and anticholinergic effects (e.g., dry mouth) are common; precise frequency bands vary by source and are not reliably standardized for this OTC product

Safety & Warnings

Contraindications

Hypersensitivity to diphenhydramine (or excipients); use in premature infants and neonates; breastfeeding (generally contraindicated/avoid). Also contraindicated with concurrent MAO inhibitor use (or within 14 days).

Warnings & Precautions

May cause significant drowsiness-avoid driving/operating machinery; avoid alcohol/other sedatives. Use caution/avoid in narrow-angle glaucoma, prostatic hypertrophy/bladder neck obstruction, pyloroduodenal obstruction, asthma/COPD (thickened secretions), cardiovascular disease/hypertension, hyperthyroidism, and hepatic impairment; paradoxical excitation may occur in children; avoid or use extreme caution in older adults due to high anticholinergic burden (Beers). Do not exceed recommended dose.

Age Restriction

OTC cough/cold use is not recommended in children <2 years; use only if specifically directed by a clinician.

Driving Warning

May Cause Drowsiness

Drug Interactions

Drug Interactions

MAO inhibitors (avoid; may intensify/prolong anticholinergic/CNS effects); alcohol and other CNS depressants (e.g., benzodiazepines, opioids, sedative-hypnotics) cause additive sedation/respiratory depression; other anticholinergics (including TCAs) increase anticholinergic burden.

Interaction Severity

MAJOR: MAO inhibitors (avoid/contraindicated-can intensify and prolong anticholinergic/CNS effects). MODERATE: other CNS depressants (alcohol, benzodiazepines, opioids, sedative-hypnotics) and other anticholinergics/TCAs (additive sedation/anticholinergic toxicity).

Alcohol Interaction

Avoid

Special Populations

Breastfeeding

Contraindicated

Children

Children 6-12 years: 12.5-25mg (4.5-9ml) every 4-6 hours, max 150mg/day. Children 2-6 years: 6.25mg (approximately 2.2ml) every 4-6 hours, max 37.5mg/day. Not recommended under 2 years.

Elderly

Use with caution; start at lowest effective dose. Diphenhydramine is listed on the Beers Criteria as potentially inappropriate in older adults due to high anticholinergic burden, risk of confusion, sedation, and falls.

Kidney Impairment

No specific dose adjustment is defined; use caution in severe renal impairment.

Storage & Patient Advice

Missed Dose

Take as soon as remembered; skip if near the time of the next dose. Do not double the dose.

Overdose

Symptoms: marked sedation or paradoxical excitation (especially children), anticholinergic toxidrome (dry mouth, mydriasis, tachycardia, hyperthermia, urinary retention), delirium/hallucinations, seizures, arrhythmias/QRS widening, respiratory depression/coma. Management: immediate emergency care/poison center; supportive care, activated charcoal if appropriate; benzodiazepines for seizures; sodium bicarbonate for wide-complex dysrhythmias; physostigmine may be considered for severe anticholinergic delirium in selected cases under expert supervision.

Patient Counseling

May cause marked drowsiness-avoid driving/operating machinery; avoid alcohol and other sedatives; use a proper measuring device and do not exceed recommended dose; do not use to make a child sleepy and avoid use in children <2 years unless directed by a clinician; seek medical advice if symptoms persist/worsen or if using other anticholinergic/CNS-depressant medicines.

Pharmacology

Mechanism of Action

First-generation H1 antihistamine (H1 receptor inverse agonist/antagonist) with significant anticholinergic (muscarinic) activity and CNS penetration causing sedation.

Onset of Action

15-30 minutes.

Duration of Effect

4-6 hours.

Half-Life

Approximately 2.4-9.3 hours in adults; may be prolonged in older adults.

Excretion

Primarily renal excretion, mostly as metabolites; only a small fraction is excreted unchanged in urine.

Protein Binding

Approximately 78-85% (high protein binding)

Product Information

Available Dosage Forms

For this SFDA-registered product: Syrup (oral).

Composition per Dose

Each 5ml: 14mg diphenhydramine hydrochloride (2.8mg/ml)

Generic Availability

Yes

Symptom Target

Allergy, Runny Nose, Cough

Sedating

Yes

Reviewed by Al Mujtama Pharmacy Medical Review Team. Last reviewed 02-05-2026