Benylin Phlegm Cough Syrup

A trusted expectorant containing 100mg guaifenesin per 5ml that helps loosen and thin phlegm, making chesty coughs easier to clear. Non-drowsy, no prescription required, and suitable for adults and adolescents aged 12 and over.

✓ Pharmacist Recommended   ✓ Loosens & Clears Phlegm   ✓ Non-Drowsy   ✓ Works Within 24 Hours   ✓ No Prescription Required

Key Benefits

• Guaifenesin works by increasing fluid flow in the airways, thinning thick, sticky phlegm so it's easier to bring up
• Addresses the underlying congestion rather than just masking the cough reflex
• Non-drowsy formula — won't interfere with your day
• Expectorant action typically begins within 24 hours
• Suitable for adults and adolescents 12 years and over

Expectorant vs Cough Suppressant — What's the Difference?

A cough suppressant stops the cough reflex, which suits a dry, irritating cough. An expectorant like guaifenesin takes a different approach — it loosens phlegm so your body can clear it more easily through coughing. For a chesty, productive cough, this is usually the more appropriate choice.

How to Use

1. Adults and adolescents 12 years and over: two 5ml spoonfuls, four times a day.
2. Do not exceed the stated dose.
3. Drink plenty of water alongside this medicine to help further loosen mucus.
4. Not suitable for children under 12 years — ask your pharmacist about age-appropriate alternatives.

Who Should Not Use This?

• Children under 12 years of age
• Anyone allergic to guaifenesin or any ingredient in the product
• Anyone with a persistent or chronic cough (e.g. asthma) or cough with excessive secretions, unless directed by a physician
• Women who are pregnant or of childbearing potential not using contraception — speak to your pharmacist or doctor first
• Anyone who is breastfeeding
• Anyone with severe liver or kidney impairment

Important Information

• If your cough persists for more than 7 days, recurs, or is accompanied by fever, rash, or persistent headache — stop use and consult your doctor
• Urine test interference: a guaifenesin metabolite can interfere with certain lab results (5-HIAA and VMA tests) if urine is collected within 24 hours of taking this product — mention this to your doctor if relevant
• Always stick to the stated dose — excess use can, in rare cases, contribute to kidney stones
• Possible side effects: gastrointestinal discomfort, nausea. Seek medical advice if symptoms are severe or persistent.

Pharmacist's Note

Benylin Mucus Cough is one I recommend for a genuinely chesty, phlegmy cough, because it works with the cough rather than against it loosening the mucus so it's easier to clear rather than suppressing the cough itself. The main thing I always check is how long the cough has been going on. If it's been more than a week, or there's a fever or persistent headache alongside it, that's the point to come in and have a proper chat rather than just continuing with the syrup. Anne Harty, Ballyduff Pharmacy

Frequently Asked Questions

What does it do?
It contains guaifenesin, an expectorant that loosens and thins phlegm, making it easier to clear from the chest.

How long does it take to work?
Expectorant action typically begins within 24 hours.

Can children take this?
No — not suitable for children under 12. Ask your pharmacist about age-appropriate alternatives.

Will it make me drowsy?
No, this formula is non-drowsy.

Can I take this if I'm pregnant?
This product is not recommended during pregnancy. Speak to your pharmacist or doctor first.

How long can I take it for?
If your cough persists beyond 7 days, recurs, or comes with fever, rash, or persistent headache — stop use and see your doctor.

Does it interfere with medical tests?
Yes — a guaifenesin metabolite can affect certain urine test results within 24 hours of taking this product. Mention this to your doctor if relevant.

Benylin Mucus Cough Syrup is a licensed Pharmacy (P) Medicine. Always read the patient information leaflet included in the pack. This page does not replace professional medical advice.

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