Lincosamide: Effects, Uses & Risks

Lincosamides are the name given to a group of antibiotics. They include the active ingredients lincomycin and clindamycin. Clindamycin is important in human medicine for treating infections of the bone, respiratory tract, and skin.

What are lincosamides?

Lincosamides are antibiotics. As such, they act against bacteria in the body. The technical chemical term for lincosamides is acylaminopyranosides. The term is explained by the chemical structure of the substance. Chemically, lincosamides are derived from pyranoses. These are monosaccharides with a six-ring structure. Medically important lincosamides are the antibiotics clindamycin and lincomycin. The active ingredient lincomycin is obtained by isolation from the bacterium Streptomyces lincolnensis. Lincomycin A, which is used medicinally, consists of propylproline and methylthiolincosaminide. Propylproline is a derivative of the amino acid proline. Methylthiolincosaminide is a derivative of octose, a C8 sugar. The compound of the two substances is an amide bond. The active ingredient clindamycin is produced semisynthetically by chlorination from lincomycin. Clindamycin is used in Germany in both human and veterinary medicine. Lincomycin is approved in the FRG only for use in veterinary medicine. In the United States and Canada, it is also used in human medicine.

Pharmacological action

Lincosamides have a bacteriostatic effect in the body. They inhibit the growth of bacteria. The antibiotics from the lincosamide group are also called protein synthesis inhibitors. They inhibit the protein synthesis of bacteria by binding to the 50-S subunit of the bacteria’s ribosomes. This prevents them from producing proteins necessary for further growth. Lincomycin works well against Gram-positive pathogens. These include streptococci and staphylococci. After administration, the substance enters the body’s own macrophages. There it accumulates and is transported by the cells to the site of action. The active substance is broken down by the liver. The substance is in turn excreted in the urine and feces. In addition to its bacteriostatic effect, clindamycin can also have a bactericidal effect at high doses, i.e. it kills the bacteria. The active ingredient can also be used to treat infections caused by gram-positive aerobic pathogens such as streptococci and staphylococci. Clindamycin is also effective against Gram-negative anaerobes and chlamydia. Toxoplasma gondii, the causative agent of toxoplasmosis, can be treated with a combination of clindamycin and the active ingredient pyrimethamine. Clindamycin is readily absorbed when taken orally. 90% of the active ingredient is absorbed and transported to the site of infection via binding to plasma proteins. In addition to internal organs, body fluids such as the pleural and synovial fluids, and tissues such as skin and bone marrow are reached by the drug. Clindamycin can cross the placenta and thus pass to the fetus in pregnant women. The active substance also passes into breast milk. Clindamycin is also broken down by the liver. Excretion occurs through feces and urine.

Medicinal use and application

Lincomycin is used in veterinary medicine in Germany mainly to treat infectious diseases of the respiratory tract, skin, and eyes. The active ingredient is administered perorally, intramuscularly, or intravenously. Clindamycin is used in human medicine to treat various infections. The active ingredient can be given orally or intravenously. One use is in the treatment of osteomyelitis, an inflammation of the bone. It can occur as part of the diabetic foot syndrome. Chronic osteomyelitis can also be treated with clindamycin. Mainly when the infection is caused by the pathogen Staphylococcus aureus. Bacterially caused joint inflammation, septic arthritis, is another possible application of the drug. In dentistry, the active ingredient is used to treat infections in the oral cavity. Another area of application for clindamycin is inflammatory skin disease such as boils or abscesses. The active ingredient is also used to treat acne. Erysipelas (erysipelas), an area-wide inflammation of the skin caused by infection with streptococci, can also be treated with clindamycin. The active ingredient is used to treat infections of the upper and lower respiratory tract.These include inflammation of the tonsils, pharynx and sinuses, as well as bronchitis, pneumonia and lung abscess. In gynecology, clindamycin is used to treat inflammation of the endometrium, fallopian tubes and ovaries, as well as infection with chlamydia. Clindamycin is considered a replacement antibiotic for patients allergic to penicillin.

Risks and side effects

Lincosamides have the same mode of action as the macrolide antibiotic group. As a result, cross-resistance may develop between macrolides and lincosamides. Lincomycin must not be used orally in herbivores because intestinal inflammation can occur with a fatal outcome. Side effects of the drug may include diarrhea and vomiting. Clindamycin, like many other antibiotics, can cause pseudomembranous enterocolitis. In this inflammation of the intestine, antibiotic use causes an imbalance of intestinal bacteria. The bacterium Clostridium difficile can proliferate. It secretes those toxins that trigger the intestinal disease. Pseudomembranous enterocolitis is manifested by severe diarrhea with fluid loss. It is a serious disease that can be fatal. Clindamycin may cause allergic reactions. Nausea, vomiting, and diarrhea may occur after ingestion. Transient change in blood count and liver enzymes have been observed. Very rarely, transient hepatitis with jaundice and the occurrence of joint inflammation have also been described.