Mixing nebuliser solutions
Nebuliser solutions should not be mixed unless there is evidence that they are compatible. Compatibility studies generally research preservative-free formulations, and mixing with these is preferable. It has been shown that the presence of stabilisers and preservatives in nebuliser combinations reduces the effect of the medication.
Mixing should be done immediately before administration, and any remaining admixture should be discarded. If turbidity, colour changes, or precipitation occur, the mixture should be discarded.
Stability of combined nebuliser solutions
Combining different nebuliser solutions can affect the chemical stability, particle size, and distribution of the medicine through the lungs. If mixing is required, the mixture should have been tested for chemical and physical compatibility before administration.
Licensed combinations
Licensed combinations of nebuliser solutions are always stated in the Summary of Product Characteristics (SPC). Whenever possible, licensed combinations should be used.
Commonly used licensed combinations
Ipratropium bromide containing
Ipratropium bromide can be combined with a short acting beta2-agonist (e.g. salbutamol) where co-administration is required.
Budesonide containing
Similarly, budesonide nebules can be mixed with terbutaline, salbutamol, sodium cromoglicate or ipratropium bromide, as long as the admixture is used within 30 minutes.
Unlicensed combinations
Unless otherwise stated, all resultant combinations of nebulised medicines are unlicensed.
If prescribing an unlicensed medicine, you must:
- be satisfied that there is sufficient evidence or experience of using the medicine to demonstrate its safety and efficacy
- take responsibility for prescribing the medicine and for overseeing the patient’s care
- make a legible record of all medicines prescribed and your reasons for prescribing an unlicensed medicine
If you are administering an unlicensed nebulised combination, you must keep a record of:
- how you have combined the nebulised solutions
- what nebulised solutions have been combined
Three-way combinations (unlicensed)
This is typically used as therapy for cystic fibrosis (CF). A number of these combinations have been found to be compatible, including:
- salbutamol combined with tobramycin and ipratropium bromide
- salbutamol combined with ipratropium bromide and dornase alfa, when all solutions are preservative free
- budesonide combined with fenoterol and ipratropium bromide
Four-way combinations with colistimethate (unlicensed)
During resistant infections, people with CF may require inhalation treatment of colistimethate with standard inhalation therapy.
The following four-way combination is compatible when preservative free solutions are used:
- colistimethate, ipratropium bromide, salbutamol, and fluticasone-17-propionate
Compatibility tool
The tool below identifies if two nebuliser solutions are compatible when combined in one nebuliser. To use this tool, select which nebuliser solutions are being combined.
Contact Details
For further information or advice on mixing nebuliser solutions, please contact your local medicines information service.