Which to choose?
They are practically the same drug (bromhexine is converted into ambroxol): the difference is presentation and dosing, not effectiveness, which is modest for both. Drinking fluids helps most. Never combine with a cough suppressant (it would stop the mucus coming up) and never give under 2 years. High fever, breathlessness, blood in the mucus or a cough lasting over 3 weeks: refer. Neither is widely marketed in the UK.
Point-by-point comparison
| Ambroxol | Bromhexine | |
|---|---|---|
| Mechanism | Thins mucus and helps clear it. It is the active metabolite of bromhexine. | Thins mucus; the liver converts it into ambroxol. |
| Indications | Productive cough with thick mucus. | Productive cough with thick mucus. |
| Adult dose | 30 mg every 8 h for the first days; then every 12 h. | 8 mg every 8 h. |
| Onset of effect | Variable; the clinical effect shows over days. | Variable; the clinical effect shows over days. |
| Duration of effect | 6-12 h | 6-8 h |
| Pregnancy | Avoid in the 1st trimester. | Avoid in the 1st trimester. |
| Breastfeeding | Passes into milk: not recommended. | Passes into milk: not recommended. |
| Paediatric use | Contraindicated under 2 years (Spanish regulator). | Contraindicated under 2 years (Spanish regulator). |
| Advantages | It is the active form: no hepatic activation needed. Throat lozenges with a local anaesthetic effect. | Long experience of use. Syrup and tablet presentations. |
| Disadvantages | Modest clinical benefit. Rare severe skin reactions and anaphylaxis (EMA 2015). | Modest clinical benefit. Stomach upset. Rare severe skin reactions and anaphylaxis (EMA 2015). |
Source: Spanish SmPC and under-2 restriction (AEMPS), EMA/PRAC 2015
Frequently asked questions
Which is better, ambroxol or bromhexine?
They are practically the same drug (bromhexine is converted into ambroxol): the difference is presentation and dosing, not effectiveness, which is modest for both. Drinking fluids helps most. Never combine with a cough suppressant (it would stop the mucus coming up) and never give under 2 years. High fever, breathlessness, blood in the mucus or a cough lasting over 3 weeks: refer. Neither is widely marketed in the UK.
Can ambroxol or bromhexine be taken in pregnancy?
Ambroxol: Avoid in the 1st trimester. Bromhexine: Avoid in the 1st trimester. Always ask a doctor or pharmacist before taking a medicine in pregnancy.
And while breastfeeding?
Ambroxol: Passes into milk: not recommended. Bromhexine: Passes into milk: not recommended.