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Prescription Antibiotics Overview
Antibiotics are antimicrobial medications that kill or inhibit the growth of bacteria. Antibiotics are used to treat infections caused by bacteria. What conditions require treatment with antibiotics? Infectious disease and conditions treated with antibiotics: Sexually transmitted infections (STIs)
Ear, nose, and throat infections:
Lower respiratory tract infections:
Urinary tract infections:
Skin and skin structure infections
Other infections:
The different types of antibiotics are known as classes. Different antibiotics destroy bacteria in different ways and treat different infections. Antibiotics within a class generally have similar effectiveness, mechanism of action and resistance, spectrum of antimicrobal activity, and side effects potential. Major classes of antibiotic drugs includ:
Some antibiotics are "bactericidal", meaning that they work by killing bacteria. Other antibiotics are "bacteriostatic", meaning that they work by stopping the growth or multiplication of bacteria. Penicillin was the the first antibiotic re-discovered by Alexander Fleming in 1929 as a natural product produced by Penicillium notatum mold. Penicillin is still one of the most useful and important antibiotics. Penicillins are bacteriocidal, they kill bacteria by inhibiting the formation of the bacterial cell wall, causing the walls to break down. Penicillins are used to treat strep throat, tonsillitis, skin infections, urinary tract infections, dental infections, ear infections, gonorrhea. Penicillins are sometimes combined with other ingredients called beta-lactamase inhibitors, which protect the penicillin from bacterial enzymes that may destroy it before it can do its work. Penicillins are usually very safe. The greatest risk is an allergic reaction, which can be severe.
Cephalosporins are one of the most widely used antibiotics. Cephalosporins produce bacteriocidal effect by inhibiting bacteria cell wall formation. They treat a broader range of bacterial infections than penicillins. Cepha antibiotics are closely related to the penicillins and many people allergic to penicillins also have allergic reactions to cephalosporins. Cephalosporins are used to treat pneumonia, strep throat, staph infections, tonsillitis, bronchitis, urinary tract infections, otitis media, various types of skin infections, gonorrhea. Cephalosporins are preferred antibiotics for prevention of infection during surgery. Cephalosporins are among the most diverse classes of antibiotics, and are divided into generations. Each newer generation of cephalosporins has greater gram negative antimicrobial activity than the preceding one. The most commonly prescribed cephalosporins:
Erythromycin, the first macrolide antibiotic, was discovered in 1952. Macrolides belong to the polyketide class of natural antibiotics and are derived from Streptomyces bacteria. Macrolides bind with ribosomes from susceptible bacteria to prevent protein production. This action is mainly bacteriostatic, but can also be bactericidal at higher doses. Macrolide antibiotics are valuable alternatives to pencillins and cephalosporins for the treatment of a number of infections. Newer members of the group, azithromycin and clarithyromycin, are particularly useful for respiratory tract infections because of their high level of lung penetration. Clarithromycin has been widely used to treat Helicobacter pylori infections, the cause of stomach ulcers. Macrolides are very effective against mycoplasma, mycobacteria, and chlamydia. Macrolides cause very little allergy problems compared to the penicillins and cephalosporins. Commonly prescribed macrolide antibiotics:
Fluoroquinolones (fluoridated quinolones) are broad-spectrum synthetic antibacterial medications. Nalidixic acid was the first quinolone, introduced in 1962. Fluoroquinolones are bactericidal agents. These drugs inhibit bacteria by interfering with their ability to make DNA. This activity makes it difficult for bacteria to multiply. Fluoroquinolones are prescribed for a variety of infections, including respiratory tract infections, sexually transmitted diseases, urinary tract infections, and skin infections. Fluoroquinolones have excellent activity against most bacterial causes of infectious diarrhea. Fluoroquinolones can cause tendinitis and tendon ruptures1. Fluoroquinolones should not be given during pregnancy. Fluoroquinolone antibiotics include:
Tetracyclines were discovered in the late 1940s and were extremely popular because their antimicrobial spectrum was broader than of most other antibiotics. Because of the development of bacterial resistance to the tetracyclines, these antibiotics have lost some of their usefulness. Tetracyclines are bacteriostatic antibiotics that work by inhibiting bacterial protein synthesis. Tetracyclines are effective against a wide variety of bacteria and are used to treat acne, Rocky Mountain spotted fever, Lyme disease, chlamydia infections, respiratory tract infections, urinary tract infections, variety of sexually transmitted diseases (STD). Doxycycline is used for prophylaxis of malaria. Minocycline is an alternative to rifampin for elimination the meningococcal carrier state2. Tetracyclines should not be given to pregnant women and children under 8 years. Commonly prescribed tetracyclines are:
Related information: Sore Throat - causes, signs and symptoms, comfort measures and treatment.
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Last updated: September, 2009 |