Cotrim® is the trade name of the antibiotic cotrimoxazole, which is considered an antibiotic not belonging to the group. It is characteristic that Cotrimoxazole exists only in a fixed combination of drugs. This includes trimethoprim and sulfamethoxazole. Bactrim and Eusaprim would be the trade names of the individual preparations. The ratio in which both drugs are combined is always 1:5.
Effect
Both sulfamethoxazole and trimethoprim have an inhibitory effect on bacterial growth. The reason is the inhibition of the synthesis of bacterial folic acid. While sulfomethoxazole inhibits the enzyme dihydrofolate synthetase, trimethoprim acts on the enzyme dihydrofolate reductase. In combination both substances have a bactericidal effect.
Fields of application
Cotrim® has a broad spectrum of activity and covers both gram-positive and gram-negative pathogens. The coccus and gram-negative rods that cover Cotrim® fall under this category: Neisseria, Enterobacteriaceae, Streptococcus and Staphylococcus. Cotrim® is ineffective against Pseudomonas, Bacteroides, Clostridia and Spirochetes. Particularly good treatment is available for acute and chronic urinary tract infections, acute and chronic inflammation of the paranasal sinuses (sinusitis) and bronchitis, as well as typhoid and paratyphoid fever. Cotrim® is also used for pathogen-related intestinal diseases such as dysentery, cholera and salmonella and for pneumonia caused by the pathogen Pneumocystis carinii.
Side effects
Cotrim® has all the side effects that the sulfonamide group of substances also has. To name a few: complaints of the gastrointestinal tract, allergic reactions such as skin sensitization, fever, blood formation disorders, rare skin reactions (Lyell syndrome or Stevens-Johnson syndrome). Risk of crystallisation in the kidney and resulting kidney damage. In premature and newborn babies there is a risk of increased bilirubin levels (bilirubinemia) with accompanying yellowing of the eyes and skin (icterus). A congestion of bile acids is also observed at times (cholestasis).
Interactions
If blood-thinning medication (anticoagulants) and medication for the treatment of diabetes mellitus (oral antidiabetics, sulfonylureas), ciclospoprin A , phenytoin and thiopental are administered at the same time, the effect of the listed substances may be increased. The simultaneous administration of non-steroidal anti-inflammatory drugs (e.g. ASS 100), salicylates, probenecide (indomethacin, phenylbutazone and sulfinpyrazone) can lead to a reduced degradation of Cotrim® with a resulting increase in the concentration of the substance. The simultaneous administration of acid inhibitors (antacids) may reduce the effectiveness of Cotrim®. The parallel intake of the substance groups barbiturates, primidone and p-aminosalicylic acid can lead to an increased toxicity of Cotrim®. The combination of Cotrim® and a dehydrating drug from the thiazide group can lead to reduced blood platelets (thrombopenia).
Cotrim and alcohol – is that compatible?
The consumption of alcohol should be avoided during the therapy with Cotrimoxazole. Alcohol is broken down in the liver by two enzymes via the toxic acetaldehyde to acetic acid. Some antibiotics – including cotrimoxazole – inhibit the enzyme that breaks down acetaldehyde into acetic acid.
As a result, the intermediate product accumulates and manifests itself with nausea, vomiting, skin redness, headaches, dizziness and palpitations. Acetaldehyde is also toxic to liver cells. Since Cotrimoxazole has a half-life in the blood of about 10 hours and some effects of the drug may still be present after this time, alcohol should not be used for the first few days after stopping Cotrim.
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