Veterinary drug · Drug monograph

Bromhexine: veterinary dose and monograph

Bromhexine is a veterinary drug. A MUCOLYTIC / secretolytic (Bisolvon) that thins and loosens viscid respiratory mucus, aiding expectoration — used for productive respiratory disease in dogs, cats, horses and food animals (often as an adjunct alongside antibiotics for… Indications include productive bronchitis / pneumonia with viscid mucus (adjunct) — small and large animals; respiratory disease where improving mucus clearance helps (e.g. with antibiotic therapy); enhancement of antibiotic penetration into bronchial secretions (e.g. with oxytetracycline). This monograph lists 5 reference doses for dogs, cats, cattle, horses and pigs, each with route, frequency and source, plus meat and milk withdrawal periods for food animals.

At a glance

Drug class: Veterinary drug
Also known as: Bisolvon, Bromhexine HCl
Species with doses: Dogs, Cats, Cattle, Horses and Pigs
General dose range: 0.5–2 mg/kg PO q12–24h — check the species tables for the indication
Routes: PO, IM
Last reviewed: 1 October 2026

Indications

Productive bronchitis / pneumonia with viscid mucus (adjunct) — small and large animals
Respiratory disease where improving mucus clearance helps (e.g. with antibiotic therapy)
Enhancement of antibiotic penetration into bronchial secretions (e.g. with oxytetracycline)

Bromhexine dose by species

Doses are per administration unless stated. mg/kg doses scale with body weight; per-animal, per-quarter and infusion-rate doses are shown as the reference writes them.

Dogs

Bromhexine doses for dogs
Indication	Dose	Route	Frequency	Duration
Mucolytic (respiratory)	0.5–2 mg/kg	PO	q12h	—

Mucolytic (respiratory): ~1–2 mg/kg PO q12h (or per product); adjunct to specific therapy. No Papich 5e or Plumb’s monograph — dose from product labelling; follow the local label.

Cats

Bromhexine doses for cats
Indication	Dose	Route	Frequency	Duration
Mucolytic (respiratory)	0.5–1 mg/kg	PO	q12–24h	—

Mucolytic (respiratory): ~0.5–1 mg/kg. No Papich 5e or Plumb’s monograph — dose from product labelling; follow the local label.

Cattle

Bromhexine doses for cattle
Indication	Dose	Route	Frequency	Duration	Withdrawal
Respiratory disease (adjunct, enhances antibiotic penetration)	0.5–1 mg/kg	IM	q24h	—	no slaughter withdrawal

Respiratory disease (adjunct, enhances antibiotic penetration): Often combined with antibiotics; observe label withdrawal. No Papich 5e or Plumb’s monograph — dose and withdrawal from product labelling; follow the local label.

Horses

Bromhexine doses for horses
Indication	Dose	Route	Frequency	Duration
Respiratory mucolysis	0.1–0.25 mg/kg	PO	q12h	—

Respiratory mucolysis: Adjunct for inflammatory airway disease. No Papich 5e or Plumb’s monograph — dose from product labelling; follow the local label.

Pigs

Bromhexine doses for pigs
Indication	Dose	Route	Frequency	Duration	Withdrawal
Respiratory disease (mucolytic adjunct)	0.5–1 mg/kg	IM	q24h	—	no slaughter withdrawal

Respiratory disease (mucolytic adjunct): No Papich 5e or Plumb’s monograph — dose and withdrawal from product labelling (IM, or in-feed/in-water per product); follow the local label.

Buffalo

No buffalo-specific doses are on file, so buffalo are dosed as cattle.

Bromhexine doses for buffalo
Indication	Dose	Route	Frequency	Duration	Withdrawal
Respiratory disease (adjunct, enhances antibiotic penetration)	0.5–1 mg/kg	IM	q24h	—	no slaughter withdrawal

Respiratory disease (adjunct, enhances antibiotic penetration): Often combined with antibiotics; observe label withdrawal. No Papich 5e or Plumb’s monograph — dose and withdrawal from product labelling; follow the local label.

Contraindications

Known hypersensitivity. Gastric ulceration (caution — may increase gastric secretion). Otherwise minimal. Address the underlying infection (it is an adjunct, not a primary antimicrobial).

Adverse effects

Generally very well tolerated
Occasional GI upset (nausea/vomiting)
Rare hypersensitivity

Drug interactions

Antibiotics (oxytetracycline, amoxicillin, erythromycin): bromhexine increases their bronchial-secretion levels (a beneficial adjunct effect)
Antitussives: avoid combining strong cough suppressants with a mucolytic (you want to clear, not retain, mucus)
No major adverse pharmacokinetic interactions

Pregnancy and lactation

Considered low-risk; long use record. Use if needed.

Monitoring

Respiratory response (easier, more productive cough; resolution of signs)
GI tolerance
Ensure the primary cause (infection/inflammation) is being treated

Toxicity and overdose

Very wide safety margin — overdose typically causes only mild GI upset. No significant organ toxicity at therapeutic or modestly supratherapeutic doses.

Management: Supportive only; no specific antidote needed. Manage GI upset symptomatically.

Clinical pearls

A safe, cheap mucolytic adjunct (very common in India) — thins viscid mucus and aids clearance in bronchitis/pneumonia
Bonus: it boosts the concentration of some antibiotics (e.g. oxytetracycline) in bronchial secretions — a rational pairing
Don't combine with strong cough SUPPRESSANTS — the goal is to clear mucus, not retain it
It is an adjunct: treat the underlying infection/inflammation as well (its metabolite is ambroxol)

Mechanism of action

A secretolytic that depolymerises the acid mucopolysaccharide (mucoprotein) fibres of bronchial mucus, reducing its viscosity, and stimulates serous secretion and ciliary activity — together improving mucociliary clearance and expectoration. It also increases the concentration of certain antibiotics in bronchial secretions/sputum. Its active metabolite is ambroxol (itself a mucolytic).

Formulations and products

Syrup 0.8 mg/mL (4 mg/5 mL)
8 mg tablet
Injection / soluble powder (veterinary)
Bisolvon Vet (Boehringer Ingelheim) — Bromhexine (powder/injection/syrup), Powder / injection / syrup
Bromhexine (various) — 8 mg tablet; 4 mg/5 mL syrup, Tablet / syrup (human-label)

Storage

Syrup/tablets/injection: 15–30 °C, protect from light.

Before you use this dose

Reference doses for veterinary professionals. Confirm the dose against the product label, the patient’s condition, current guidance and local regulations before use; the attending veterinarian remains responsible for every clinical decision.

Frequently asked questions

What is the dose of Bromhexine for dogs?

Reference doses for Bromhexine in dogs: 0.5–2 mg/kg PO q12h (Mucolytic (respiratory)). Confirm against the label and the patient before use.

What is the dose of Bromhexine for cats?

Reference doses for Bromhexine in cats: 0.5–1 mg/kg PO q12–24h (Mucolytic (respiratory)). Confirm against the label and the patient before use.

What is the dose of Bromhexine for cattle?

Reference doses for Bromhexine in cattle: 0.5–1 mg/kg IM q24h (Respiratory disease (adjunct, enhances antibiotic penetration)). Confirm against the label and the patient before use.

What is the withdrawal period for Bromhexine?

Cattle, IM (Respiratory disease (adjunct, enhances antibiotic penetration)): no slaughter withdrawal; Pigs, IM (Respiratory disease (mucolytic adjunct)): no slaughter withdrawal. Follow the product label and national regulations where they differ.

When should Bromhexine not be used?