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