Topical NSAID — Throat / Mouth Pregnancy: No clinical data in pregnancy; should not be used in pregnancy unless considered essential by the physician. From week 20 onward use may cause oligohydramnios from foetal renal dysfunction, and ductus arteriosus constriction has been reported after second-trimester treatment - keep dose as low and duration as short as possible, and consider antenatal monitoring for oligohydramnios and ductus arteriosus constriction after several days' exposure from gestational week 20. CONTRAINDICATED during the third trimester (risk of premature constriction/closure of the ductus arteriosus, pulmonary hypertension, renal dysfunction, prolonged bleeding time and delayed/prolonged labour). Should not be used during lactation unless considered essential by the physician.

Benzydamine Hydrochloride

Brand names: Difflam, Difflam Forte

Benzydamine hydrochloride is a locally acting non-steroidal anti-inflammatory used as an oromucosal rinse or spray to relieve pain and inflammation of the mouth and throat, including post-tonsillectomy and oropharyngeal mucositis.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: 4 to 8 puffs of benzydamine hydrochloride 0.15% w/v oromucosal spray

Route: Oromucosal spray (SPC states 'For oral use')

Frequency: Every 1.5 to 3 hours

Dose applies to adults, adolescents and the elderly. Elderly: because of the small amount of drug applied, elderly patients can receive the same dose as adults. Paediatric dosing stated in the SPC (not a mg/kg dose, so not captured as a structured paediatric dose) - children 6 to 12 years: 4 puffs every 1.5 to 3 hours; children under 6 years: one puff to be administered per 4 kg of body weight, up to a maximum of 4 puffs, every 1.5 to 3 hours. Clinician to verify all paediatric use against a children's formulary. No maximum adult daily dose or maximum duration is stated in SPC section 4.2. Avoid contact with the eyes; if the condition is aggravated or not improved, use should cease. Source product: Benzydamine Hydrochloride 0.15% w/v Oromucosal Spray (UK SPC).

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to benzydamine hydrochloride or to any of the excipients
Third trimester of pregnancy (SPC section 4.6 states benzydamine spray is contraindicated during the third trimester)

Side effects

Oral numbness and a stinging feeling in the mouth (uncommon; described as the most common side effects - stinging has been reported to disappear on continuing treatment, but if it persists treatment should be discontinued)
Laryngospasm or bronchospasm (very rare)
Pruritus, urticaria, photosensitivity reaction and rash (very rare)
Angioedema (frequency not known)
Anaphylactic reactions and hypersensitivity reactions (frequency not known)

Interactions

None known (SPC section 4.5)

Clinical monograph

How it works

It has local analgesic, anti-inflammatory and mild local anaesthetic and antiseptic properties when applied to inflamed mucosa, with negligible systemic absorption across intact mucosa.

Prescribing in practice

Applied topically to the oropharynx only; the rinse should not be swallowed and is not a substitute for systemic antimicrobial or analgesic therapy where indicated.
Transient stinging, numbness or tingling of the mouth is common; diluting the rinse with water can reduce this if it occurs.
Use is short-term for symptomatic relief; review if symptoms persist or worsen rather than continuing indefinitely.

Monitoring

No routine laboratory monitoring is required; reassess if oropharyngeal symptoms fail to settle or local irritation persists.

Counselling the patient

Gargle or rinse and then spit out; do not swallow the solution.
A brief stinging or numb sensation is expected and settles quickly.
Seek review if mouth or throat symptoms persist beyond a few days.

Evidence & guidelines

Topical benzydamine is an established symptomatic treatment for oropharyngeal pain and is recommended for radiation-induced oral mucositis in supportive-care guidance.

Reference: Cochrane Review (Clarkson et al. 2014) Oral Mucositis; NICE NG84; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways