Monday, October 12, 2009

Colistin: An overview

Colistin / Hydrocortisone / Neomycin

Generic Name: Colistin/Hydrocortisone/Neomycin (koe-LIS-tin/hye-droe-KOR-ti-sone/nee-oh-MYE-sin)
Brand Name: Coly-Mycin S Otic

Colistin/Hydrocortisone/Neomycin is used for:

Treating infections of the ear caused by certain bacteria. It may also be used for other conditions as determined by your doctor.

Colistin/Hydrocortisone/Neomycin is a combination of 2 antibiotics and a corticosteroid. The antibiotics work by killing sensitive bacteria. The corticosteroid reduces inflammation.

Contraindications for use - Do Not Use

  • you are allergic to any ingredient in Colistin/Hydrocortisone/Neomycin , to other aminoglycosides (eg, gentamicin), or to other corticosteroids (eg, prednisone)
  • you have a viral infection of the ear (eg, herpes simplex, chickenpox, shingles)
  • you have a perforated ear drum

Contact your doctor or health care provider right away if any of these apply to you.

Before using Colistin/Hydrocortisone/Neomycin

Some medical conditions may interact with Colistin/Hydrocortisone/Neomycin . Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

  • if you are pregnant, planning to become pregnant, or are breast-feeding
  • if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
  • if you have allergies to medicines, foods, or other substances
  • if you have the blood disease porphyria

Some MEDICINES MAY INTERACT with Colistin/Hydrocortisone/Neomycin . Because little, if any, of Colistin/Hydrocortisone/Neomycin is absorbed into the blood, the risk of it interacting with another medicine is low.

Ask your health care provider if Colistin/Hydrocortisone/Neomycin may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.


Colistin: An overview

INTRODUCTION

Colistin (also called polymyxin E) belongs to the polymyxin group of antibiotics [1]. It was first isolated in Japan in 1949 from Bacillus polymyxa var. colistinus, and became available for clinical use in 1959 [2,3]. Colistin was given as an intramuscular injection for the treatment of Gram negative infections but fell out of favor after aminoglycosides became available because of its significant side effects. It was later used as topical therapy as part of selective digestive tract decontamination and is still used in aerosolized form for patients with cystic fibrosis.

More recently, a number of centers around the world have used colistin intravenously for otherwise panresistant nosocomial infections, especially those due to Pseudomonas and Acinetobacter spp [4-8].

The spectrum of activity, mechanisms of action and resistance, pharmacokinetics, interactions with other drugs, and adverse effects of colistin will be reviewed here. The clinical settings in which colistin may be used are discussed separately in the appropriate topic reviews.

MECHANISM OF ACTION

— Colistin is a bactericidal drug that binds to lipopolysaccharides and phospholipids in the outer cell membrane of gram-negative bacteria. It competitively displaces divalent cations from the phosphate groups of membrane lipids, which leads to disruption of the outer cell membrane, leakage of intracellular contents, and bacterial death [3,9,10].

In addition to its bactericidal effect, colistin can bind and neutralize lipopolysaccharide (LPS) and prevent the pathophysiologic effects of endotoxin in the circulation [11,12].

(Excerpt - UpToDate)