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