Colistin sulphomethate: Product change
The supplier, Link, plans to stop supplying their brand of colistin sulphomethate inj 150 mg, 2 ml vial (Colistin-Link | Pharmacode 2245418) due to low demand.
14 March 2025 Update
The remaining stock of Colistin-Link expires on 31 May 2025. It will be delisted from the Pharmaceutical Schedule from 1 June 2025.
Affected product
Link plans to discontinue supply of the following product. Stock will expire on 31 May 2025. The product will be delisted from 1 June 2025.
- Chemical: Colistin sulphomethate
- Presentation: Inj 150 mg, 2 ml vial
- Brand: Colistin-Link
- Pharmacode: 2245418
- Subsidy: $65.00
- Pack Size: Per 1
Alternative product
Link has sourced an alternative colistin sulphomethate product, colistin sulphomethate inj 2 million IU, 10 ml vial (Colomycin). This was funded from 1 March 2025.
- Chemical: Colistin sulphomethate
- Presentation: Inj 2 million iu, 10 ml vial
- Brand: Colomycin
- Pharmacode: 2698005
- Subsidy: $216.67
- Pack Size: Per 10
Key differences between Colistin-Link and Colomycin:
- Colomycin has different approved indications listed on the datasheet, primarily due to additional routes of administration (including inhalation and intrathecal)
- The labelling and product information of Colomycin uses IU antibiotic activity to describe the strength, rather than mg equivalent like Colistin-Link.
- Colomycin comes in a 10 ml vial containing 2 million IU, Colistin-Link comes in a 2 ml vial containing 4.5 million IU.
- Colomycin has different instructions for reconstitution and dilution (including different compatible fluids)
Clinical advice from members of our Anti-Infective and Respiratory Advisory Committees has indicated Colomycin is a suitable alternative.
Datasheets
Consumer Medicine Information (CMI)
COLISTIN LINK® Consumer Medicine Information (CMI) | Medsafe [PDF](external link)
Table of differences between Colistin-Link and Colomycin:
|
|
COLISTIN-LINK® 150 mg/2 mL vial, powder for injection |
COLOMYCIN 2 million IU/10 mL vial, powder for solution for injection, infusion or inhalation |
|
Active drug |
colistin sulphomethate |
colistin sulphomethate |
|
Strength |
Each vial contains colistin 150 mg, the equivalent of 4,500,000 IU antibiotic activity. |
Each vial contains 2 million IU colistimethate sodium.
|
|
Excipients |
Nil |
Nil |
|
Vial size |
2 mL |
10 mL |
|
Pack Size |
1 vial |
10 vials |
|
Unit of Strength on label |
Mg |
IU |
|
Administration |
IV or IM |
IV or inhalation, or intrathecally |
|
Medsafe approved |
Yes |
No |
|
Reconstitution |
Please refer to information leaflets for detailed information. The vial should be reconstituted with 2.0 mL sterile water for injections. The reconstituted solution provides 150 mg colistin in 2 mL. During reconstitution swirl gently to avoid frothing |
Please refer to information leaflets for detailed information. For bolus injection: The vial should be reconstituted with not more than 10 ml sterile water for injection or 0.9% sodium chloride. For infusion: The contents of the reconstituted vial may be diluted, usually with 50 ml 0.9% sodium chloride. When the intrathecal and intraventricular routes of administration are used, the volume administered should not exceed 1 ml (reconstituted concentration 125,000 IU/ml). For inhalation by nebuliser: The vial should be reconstituted with either water for injections or 0.9% sodium chloride. |
|
Shelf life (unopened vials) |
36 months |
36 months |
|
Storage (unopened vials) |
Store below 25°C |
Store below 25°C |
|
Stability after preparation |
Please refer to information leaflets for detailed information. Once reconstituted, store the solution at 2°C to 8°C (Refrigerate. Do not freeze). Contains no additional antimicrobial agent, use in one patient on one occasion only, as soon as practicable after reconstitution. Reconstituted solution must be used within 24 hours. |
Please refer to information leaflets for detailed information. Depending on concentration of solution and route of administration, stability varies between use immediately and 24 hours at 2 to 8°C. |
Dose conversion table
|
Potency |
≈ mass of CMS (mg) * |
|
|
IU |
≈ mg CBA |
|
|
12 500 |
0.4 |
1 |
|
150 000 |
5 |
12 |
|
1 000 000 |
34 |
80 |
|
4 500 000 |
150 |
360 |
|
9 000 000 |
300 |
720 |
Prescribing and supplying an unapproved medicine
Colomycin is not Medsafe registered. (It is approved for use in the United Kingdom). This means it has to be prescribed and dispensed in line with section 29 of the Medicines Act 1981 allows for medicines that are not Medsafe approved to be prescribed and supplied to people. The medicine must be prescribed by someone registered with the Medical Council of New Zealand – such as, a doctor.
We know supplying a medicine under section 29 is not ideal. In this case, however, this will allow patients to be able to access an appropriate treatment. We are continuing to look for a registered alternative.
We apologise for any inconvenience this causes.
Advice for prescribing under section 29 – BPAC website(external link)
Prescriber and pharmacist requirements for section 29 medicines – Medsafe website (external link)
Medsafe’s section 29 Declaration / Notification Form [DOC](external link)
What patients need to know about unapproved medicines – Healthify website(external link)
Who to contact
If you have questions about this issue, email enquiry@pharmac.govt.nz
Please include as much information as you can about the product (presentation, brand, Pharmacode) and who your wholesaler is.
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