Formulary
Colistimethate sodium: Indications, Dosing, Side Effects and Interactions
The polymyxin antibiotic, colistimethate sodium (colistin sulfomethate sodium), is active against Gram-negative organisms including Pseudomonas aeruginosa ,...
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Colistimethate sodium: Indications, Dosing, Side Effects and Interactions
The polymyxin antibiotic, colistimethate sodium (colistin sulfomethate sodium), is active against Gram-negative organisms including Pseudomonas aeruginosa ,...
Drug action
The polymyxin antibiotic, colistimethate sodium (colistin sulfomethate sodium), is active against Gram-negative organisms including Pseudomonas aeruginosa , Acinetobacter baumanii , and Klebsiella pneumoniae . It is not absorbed by mouth and thus needs to be given by injection for a systemic effect.
Indications and dose
**Serious infections due to selected aerobic Gram-negative bacteria in patients with limited treatment options**
- **Adult** (By Intravenous Infusion): 9 million units daily in 2-3 divided doses, an initial loading dose of 9 million units should be used in those who are critically ill, loading and maintenance doses of up to 12 million units may be required in some cases, however clinical experience is limited and safety has not been established-consult product literature for details.
**Management of chronic pulmonary infections due toPseudomonas aeruginosain patients with cystic fibrosis**
- **Child** (By Inhalation Of Nebulised Solution): Management of chronic pulmonary infections due to Pseudomonas aeruginosa in patients with cystic fibrosis 2-17 years 1-2 million units 2-3 times a day, for specific advice on administration using nebulisers-consult product literature; maximum 6 million units per day.
- **Adult** (By Inhalation Of Nebulised Solution): 1-2 million units 2-3 times a day, for specific advice on administration using nebulisers-consult product literature; maximum 6 million units per day.
- **Adult** (By Inhalation Of Powder): 1.66 million units twice daily.
**Serious infections due to selected aerobic Gram-negative bacteria in patients with limited treatment options for colistimethate sodium**
- **Neonate** (By intravenous infusion): 25 000-50 000 units/kg 3 times a day, the data supporting the dose regimen are very limited-consult product literature for available information, including recommendation to use lean body-weight for dosing.
- **Child (body-weight up to 41 kg)** (By intravenous infusion): 25 000-50 000 units/kg 3 times a day, the data supporting the dose regimen are very limited-consult product literature for available information, including recommendation to use lean body-weight for dosing.
- **Child (body-weight 41 kg and above)** (By intravenous infusion): 4.5 million units twice daily, the data supporting the dose regimen are very limited-consult product literature for available information, including recommendation to use lean body-weight for dosing, alternatively 3 million units 3 times a day, the data supporting the dose regimen are very limited-consult product literature for available information, including recommendation to use lean body-weight for dosing.
**Management of chronic pulmonary infections due to Pseudomonas aeruginosa in patients with cystic fibrosis for colistimethate sodium**
- **Child 1-23 months** (By inhalation of nebulised solution): 0.5-1 million units twice daily, for specific advice on administration using nebulisers-consult product literature; maximum 2 million units per day.
- **Child 2-17 years** (By inhalation of nebulised solution): 1-2 million units 2-3 times a day, for specific advice on administration using nebulisers-consult product literature; maximum 6 million units per day.
- **Child 6-17 years** (By inhalation of powder): 1.66 million units twice daily.
Cautions
General cautions: Children under 1 year of age (effects of immature renal and metabolic function on conversion to active colistin not known) (in children) Specific cautions: When used by inhalation Severe haemoptysis-risk of further haemorrhage
Contraindications
Myasthenia gravis
Side effects
Common or very common When used by inhalation Arthralgia; asthenia; asthma; balance impaired; chest discomfort; cough; dysphonia; dyspnoea; fever; haemorrhage; headache; lower respiratory tract infection; nausea; respiratory disorders; taste altered; throat complaints; tinnitus; vomiting Uncommon When used by inhalation Anxiety; appetite decreased; diarrhoea; drowsiness; ear congestion; flatulence; oral disorders; proteinuria; seizure; sputum purulent; thirst; weight change Rare or very rare With parenteral use Confusion; nephrotoxicity; presyncope; psychosis; speech slurred; visual impairment Frequency not known With parenteral use Apnoea; neurological effects; neurotoxicity; renal disorder; sensory disorder Side-effects, further information Neurotoxicity and nephrotoxicity are dose-related.
Interactions
**Other interactions (1):**
- Co-treatment with colistimethate sodium and macrolides such as azithromycin and clarithromycin, or fluoroquinolones such as norfloxacin and ciprofloxacin should be undertaken with caution in...
Pregnancy
When used by inhalation: Clinical use suggests probably safe. With intravenous use: Manufacturer advises use only if potential benefit outweighs risk.
Breast feeding
Present in milk but poorly absorbed from gut; manufacturers advise avoid (or use only if potential benefit outweighs risk).
Hepatic impairment
With intravenous use: Manufacturer advises caution (no information available).
Renal impairment
When used by inhalation: Manufacturer advises caution. With intravenous use in children: Consult product literature. Dose adjustments With intravenous use in adults: Manufacturer advises reduce maintenance dose if creatinine clearance less than 50 mL/minute-consult product literature. Monitoring With intravenous use: In renal impairment, monitor plasma colistimethate sodium concentration during parenteral treatment-consult product literature. Recommended 'peak' plasma colistimethate sodium concentration (approx. 1 hour after intravenous injection or infusion) 5-15 mg/litre; pre-dose ('trough') concentration 2-6 mg/litre.
Medicinal forms
Solution,Powder,Solution
Clinical governance
**Author:** MedNext Clinical Team. **Clinical reviewer:** Dr Shameer Deen, MBBS, MS, MRCS. **Sources:** BNF, Indian Pharmacopoeia, CIMS India. **Correction:** Report errors at support@mednext.academy.
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