| An antibiotic is a drug that kills or slows the growth | | | | |
| of bacteria. Antibiotics are one class of antimicrobials, | | | | First generation |
| a larger group which also includes anti-viral, anti-fungal, | | | | |
| and anti-parasitic drugs. Antibiotics are chemicals | | | | cephazolin |
| produced by or derived from microorganisms (i.e. | | | | cefadroxil |
| bugs or germs such as bacteria and fungi). The first | | | | cephalexin |
| antibiotic was discovered by Alexander Fleming in | | | | cephradine |
| 1928 in a significant breakthrough for medical | | | | |
| science.Antibiotics are among the most frequently | | | | Second generation |
| prescribed medications in modern medicine. | | | | |
| Some antibiotics are 'bactericidal', meaning that they | | | | cefaclor |
| work by killing bacteria. Other antibiotics are | | | | cefuroxime |
| 'bacteriostatic', meaning that they work by stopping | | | | cefprozil |
| bacteria multiplying.Each different type of antibiotic | | | | loracarbef |
| affects different bacteria in different ways. For | | | | |
| example, an antibiotic might inhibit a bacterium's ability | | | | Third generation |
| to turn glucose into energy, or its ability to construct | | | | |
| its cell wall. When this happens, the bacterium dies | | | | cefotaxime |
| instead of reproducing.Some antibiotics can be used | | | | cefixime |
| to treat a wide range of infections and are known as | | | | cefpodoxime |
| 'broad-spectrum' antibiotics. Others are only effective | | | | ceftazidime |
| against a few types of bacteria and are called | | | | cefdinir |
| 'narrow-spectrum' antibiotics.Side effects of | | | | |
| antibioticsAntibiotics can literally save lives and are | | | | Fourth generation |
| effective in treating illnesses caused by bacterial | | | | |
| infections. However, like all drugs, they have the | | | | cefepime |
| potential to cause unwanted side effects. Many of | | | | cefpirome |
| these side effects are not dangerous, although they | | | | |
| can make life miserable while the drug is being | | | | FluoroquinolonesFluoroquinolones are known as |
| taken.In general, antibiotics rarely cause serious side | | | | broad-spectrum antibiotics, meaning they are |
| effects. The most common side effects from | | | | effective against many bacteria. Fluoroquinolones are |
| antibiotics are diarrhea, nausea, vomiting. Fungal | | | | used to treat most common urinary tract infections, |
| infections of the mouth, digestive tract and vagina | | | | skin infections, and respiratory infections (such as |
| can also occur with antibiotics because they destroy | | | | sinusitis, pneumonia, bronchitis). Common side effects |
| the protective 'good' bacteria in the body (which help | | | | of fluoroquinolones include mainly the digestive |
| prevent overgrowth of any one organism), as well as | | | | system: mild stomach pain or upset, nausea, vomiting, |
| the 'bad' ones, responsible for the infection being | | | | and diarrhea. These are usually mild and go away |
| treated.Some people are allergic to antibiotics, | | | | over time. Fluoroquinolones should not be given during |
| particularly penicillins. Allergic reactions cause swelling | | | | pregnancy.Fluoroquinolones inhibit bacteria by |
| of the face, itching and a skin rash and, in severe | | | | interfering with their ability to make DNA. This |
| cases, breathing difficulties. Allergic reactions require | | | | activity makes it difficult for bacteria to multiply. This |
| prompt treatment.Types of antibioticsThere are | | | | effect is bacteriocidal.The most commonly-prescribed |
| many different kinds of antibiotics. The type of | | | | fluoroquinolones: |
| antibiotics you take depends on the type of infection | | | | |
| you have and what kind of antibiotics are known to | | | | ciprofloxacin |
| be effective.The main classes of antibiotics: | | | | gatifloxacin |
| | | | gemifloxacin |
| Aminoglycosides | | | | levofloxacin |
| Cephalosporins | | | | moxifloxacin |
| Fluoroquinolones | | | | norfloxacin |
| Macrolides | | | | ofloxacin |
| Penicillins | | | | trovafloxacin |
| Tetracyclines | | | | PenicillinsPenicillin was the first antibiotic discovered |
| MacrolidesThere are a couple of new relatives of | | | | by Alexander Fleming in 1929. Penicillins are used to |
| erythromycin (azithromycin and clarithromycin) that | | | | treat skin infections, dental infections, ear infections, |
| work the same way, but kill more bugs and have | | | | respiratory tract infections, urinary tract infections, |
| slightly fewer side effects. The erythromycin-like | | | | gonorrhea. Penicillins are sometimes combined with |
| antibiotics are also known as macrolides. Macrolides | | | | other ingredients called beta-lactamase inhibitors, |
| belong to the polyketide class of natural products. | | | | which protect the penicillin from bacterial enzymes |
| Macrolide antibiotics are used to treat respiratory | | | | that may destroy it before it can do its |
| tract infections, genital, gastrointestinal tract, soft | | | | work.Penicillins are usually very safe. The greatest risk |
| tissue infections caused by susceptible strains of | | | | is an allergic reaction, which can be severe. People |
| specific bacteria.Macrolides bind with ribosomes from | | | | who have been allergic to cephalosporins are likely to |
| susceptible bacteria to prevent protein production. | | | | be allergic to penicillins.Penicillins block the construction |
| This action is mainly bacteriostatic, but can also be | | | | of bacteria cell walls, causing the walls to break |
| bactericidal in high concentrations.Macrolides cause | | | | down, and eventually killing the bacteria.The most |
| very little allergy problems compared to the penicillins | | | | commonly-prescribed penicillins: |
| and cephalosporins, the biggest concern with these | | | | |
| medicines is that they can irritate the stomach.The | | | | amoxicillin |
| most commonly-prescribed macrolides: | | | | ampicillin |
| | | | bacampicillin |
| erythromycin | | | | oxacillin |
| clarithromycin | | | | penicillin |
| azithromycin | | | | Tetracyclines Tetracyclines are a family of antibiotics |
| roxithromycin | | | | used to treat a broad spectrum of bacterial |
| Aminoglycosides Aminoglycoside antibiotics are used | | | | infections. Tetracyclines were discovered in the late |
| to treat infections caused by gram-negative bacteria. | | | | 1940s and were extremely popular when they were |
| Aminoglycosides may be used along with penicillins or | | | | first discovered. The tetracycline antibiotics have a |
| cephalosporins to give a two-pronged attack on the | | | | very broad spectrum of action.Tetracyclines are used |
| bacteria. Aminoglycosides work quite well, but | | | | to treat mild acne, Rocky Mountain spotted fever, |
| bacteria can become resistant to them. Since | | | | Lyme Disease, upper respiratory tract infections, |
| aminoglycosides are broken down easily in the | | | | urinary tract infections, sexually transmitted diseases, |
| stomach, they can't be given by mouth and must be | | | | typhus.The most commonly-prescribed tetracyclines: |
| injected. When injected, their side effects include | | | | |
| possible damage to the ears and to the kidneys. This | | | | tetracycline |
| can be minimized by checking the amount of the | | | | doxycycline |
| drug in the blood and adjusting the dose so that | | | | minocycline |
| there is enough drug to kill bacteria but not too much | | | | Antibiotic resistanceAntibiotics are extremely |
| of it. Generally, aminoglycosides are given for short | | | | important in medicine, but unfortunately bacteria are |
| time periods.The aminoglycosides are drugs which | | | | capable of developing resistance to them. |
| stop bacteria from making proteins. This effect is | | | | Antibiotic-resistant bacteria are germs that are not |
| bactericidal.The most commonly-prescribed | | | | killed by commonly used antibiotics. When bacteria |
| aminoglycosides: | | | | are exposed to the same antibiotics over and over, |
| | | | the bacteria can change and are no longer affected |
| amikacin | | | | by the drug.Bacteria have number of ways how they |
| gentamicin | | | | become antibiotic-resistant. For example, they |
| kanamycin | | | | possess an internal mechanism of changing their |
| neomycin | | | | structure so the antibiotic no longer works, they |
| streptomycin | | | | develop ways to inactivate or neutralize the antibiotic. |
| tobramycin | | | | Also bacteria can transfer the genes coding for |
| CephalosporinsCephalosporins are grouped into | | | | antibiotic resistance between them, making it possible |
| "generations" by their antimicrobial properties. | | | | for bacteria never exposed to an antibiotic to acquire |
| Cephalosporins are categorized chronically, and are | | | | resistance from those which have. The problem of |
| therefore divided into first, second, and third | | | | antibiotic resistance is worsened when antibiotics are |
| generations. Currently, three generations of | | | | used to treat disorders in which they have no |
| cephalosporins are recognized and a fourth has been | | | | efficacy (e.g. antibiotics are not effective against |
| proposed. Each newer generation of cephalosporins | | | | infections caused by viruses), and when they are |
| has greater gram negative antimicrobial properties | | | | used widely as prophylaxis rather than |
| than the preceding generation. The later-generation | | | | treatment.Resistance to antibiotics poses a serious |
| cephalosporins have greater effect against resistant | | | | and growing problem, because some infectious |
| bacteria.Cephalosporins are used to treat pneumonia, | | | | diseases are becoming more difficult to treat. |
| strep throat, staph infections, tonsillitis, bronchitis, | | | | Resistant bacteria do not respond to the antibiotics |
| otitis media, various types of skin infections, | | | | and continue to cause infection. Some of these |
| gonorrhea. Cephalosporin antibiotics are also | | | | resistant bacteria can be treated with more powerful |
| commonly used for surgical prophylaxis. | | | | medicines, but there some infections that are difficult |
| Cephalosporins are closely related to the | | | | to cure even with new or experimental drugs.Yury |
| penicillins.Cephalosporins have a bacteriocidal effect by | | | | Bayarski is the author of - a prescription drug price |
| inhibiting the synthesis of the bacteria cell wall.The | | | | comparison website. |
| most commonly-prescribed cephalosporins: | | | | |