why is S. pyogenes resistant to penicillin?
553054
When you friend had pharyngitis first, the doc administered penicillin. Over time however the bacteria got 'resistant' to penicillin (most probably because either she took too much of it or did not take the penicillin on time/at regular intervals like she should have) meaning that it now has a new gene that prevents it from being affected by penicillin - thats the prob with antibiotics - on long term use most bacteria get resistant. \n\nSo now the remedy is use a stronger antibiotic that would work against the bacterial infection. Ask the doc to prescribe a stronger antibiotic, however if it is not taken regulalry, the bacteria can become antibiotic tolerant.
33539
the first answer is a very good one, but for someone who may not be in the medical profession, penicillin can be inactivated by drinking pop,orange juice, activated charcoal, alcoholic beverages...many things. if you are a medical student sorry, if you aren't ask dr and pharmacist
198655
They block the synthesis of bacteria cell wall\nBeta lactam (contain a ring- beta lactam ring) example are penicillin, cephalosporin, carbapenems\n\n\nSome bacteria now secrete beta lactamase- which stops the beta lactam from working.\n\nHowever, in such infectional bacteria, there are beta lactamase inhibitor that stop the beta lactamase from working. Example: Sulbactam.
487748
well, if you take penicillin than the chances are very high.  Strep throat will pretty much always be cured unless you have a weakened immune system.
79560
If you do a Culture & Sensitivity Lab, it will show on the Sensitivity part of the lab what antibiotics the bacteria is suseptible and resistant to.  For example, I recently came across a patient with a VRE or Vancomycin Resistant Enterococci, and the only antibiotic it was still suseptible to was Tetracycline.... yes Tetracycline
697513
Always finish the full course of anti-biotics as prescribed.  This is important to be sure that the medication has killed all of the bacteria. If you stop the anti-biotic too soon, some bacteria are of tougher strands & have the capacity to mutate into "superbugs".  \nAnti-biotic Resistance builds up due to people not finishing their prescribed doses.
121470
Your question may not be phrased correctly.  Antiobiotics are on the rise because they work and we get sick.  They are also added to animal feed to keep them healthy so we can eat them.\n\nI would think that the question you should be asking is, "Why is antiobiotic resistance on the rise today".  The answer is that our prolific use of antibiotics, even when we don't need them, has weeded out the bacteria that were most susceptible while allowing those with mild resistance to survive better from reduced competition.  Over time asthese mildly resistent bacteria are spread and further selected for my antibiotics they lead to moderate resisteance to high resistance and ultimately to complete resistance.  This doesn't make the disease worse, but they are harder to eliminate which can make the disease progress and become worse.
422182
I was told that because I had to have lots of penicillin when I was a child (sick all the time), that my "good" bacteria in my intestines was destroyed.  I need to take acidophiles daily to keep my diarhia and cramps at bay..It really works!
165247
Yes.  \n\nImproper use of antibiotics is the primary cause of the appearance of antibiotic resistant bacteria.  When antibiotics are used unnecessarily (say, in reponse to a viral infection), the bacteria that are in the patient's body but not causing disease are exposed to the antibiotics.  Those bactieria that are not resistant are killed, allowing the one or two mutant resistant to the antibiotic to florish and reproduce.\n\nAntibiotic resistance can also result from failure to complete a course of antibiotics.  Many people will take antibiotics until the feel better, and will not compelete the prescibed course.  This is a major problem because there are still some bacteria in their body, and the ones that are left are the ones that are most resistant to the antibiotics.  These resistant bacteria can then be transmitted to another person, but this time, the antibiotics won't work at all.\n\nPenicillin resistant bacteria began to appear within a few years of the drug's commercial debut at the end of World War II.  Now, penicillin is rarely used to treat serious bacteria infections as there are very few strains against which it is still effective.  Antibiotic resistant bacteria force scientists to look for new antibiotics.  The more rapidly resistance occurs, the more urgently new drugs are needed.  Science can't keep up.  Bacteria that are resistant to all known antibiotics leave the patient with no better chance of survival than he would have had 100 years ago.
438333
you may be resistant to a strain of bacteria...over time viruses/bacteria mutate and your t-cells, memory cells may not recognize them.... thus becoming prone for infection/disease.
322700
You are asking about antibiotics (cephalosporins, bacitracin, polymyxin B) and antimycotics (griseofulvin).  Actually, any germ can develop resistance to any antibiotic treatment. Plus, cephalosporins is a group of antibiotics, with 4 generations and each generation differs in efficacy against bacteria.
967690
Penicillin- lead to the discovery of various other antibiotics.  Even though antibiotic resistance is becoming a problem, antibiotics have saved so many lives.
1070128
If you mean antibiotic resistance, when an antibiotic is used inapropriatly the bacteria is not completley erradicated and the ones that survive are the ones that are inharently resistant to the drug and those produce the next generation that are at least as resistant as their parents if not more and this happens repeadedly until the antibiotic is no longer effective for that bacteria. This is why you should not take an antibiotic for your colds because those are viral infections and you are just causing bacteria to get exposed to antibiotics unnessesarily, also if you do get an antibiotic you must take all of it, dont quit taking it when you feel better and save the rest for next time, you will be doing humanity a disservice
402756
The tendency for hospitals with high prevalences of Extended-spectrum beta-lactamases is to place those patients in similar isolation status as those with vancomycin-resistant enterococci (VRE) or methicillin-resistant Staph aureus (MRSA).  That implies wearing of gloves, gowns, etc., and strict handwashing rules.  \n\nOtherwise, the tendency is to follow the susceptibility results from the cultures and to use narrow-spectrum antibiotics whenever possible.
1054868
The concept of antibiotic immunity is a misnomer that can lead people to believe that they may become "immune" or "resistant" to an antibiotic if they take it too frequently or inappropriately. This notion stems from a misunderstanding in the general public of the concept of antibiotic resistance.\nIt is not people who become immune or resistant to an antibiotic. Rather it is the bacteria responsible for infections that become resistant. The purpose of an antibiotic is to kill--or at least inhibit the growth of--bacteria to quell an infection. Bacteria have been around for thousands of years and have had to survive in hostile environments. As a result, they are able to adapt and have a number of mechanisms for survival, one of which is the development of resistance to antibiotics.\n\nMisuse or overuse of antibiotics selects for resistant bacteria. In a bacterial infection, billions of bacteria are present. Taking an antibiotic will kill or inhibit those bacteria that are susceptible to its effects and leave behind a subpopulation of bacteria that are resistant to the antibiotic. These remaining bacteria can survive and continue to grow. If they then spread from person to person, they may become the norm, and all future infections caused by these resistant bacteria will withstand the original antibiotic, rendering it useless for treatment. For many infections, patients often begin to feel better before all the bacteria have been eliminated. But it is important to complete a full course of antibiotics, even if one’s symptoms have improved, to ensure that as many bacteria as possible are destroyed.\n\nBacteria have a variety of mechanisms by which they become resistant to antibiotics, depending on the particular antibiotic (or class of antibiotic) and the type of bacteria involved. Because antibiotics work differently to attack an essential function of bacteria, it is necessary to consider both the phenotypic mechanism of resistance and the underlying genotypic mechanism of resistance.\n\nFrom a physical or biochemical perspective, there are a number of factors that contribute to antiobiotic resistance. First, the cell wall of a bacterium can be altered so that an antibiotic cannot penetrate it. Second, some bacteria produce enzymes that can destroy antibiotics before they can work. Third, certain bacteria have developed mechanisms known as efflux pumps, which are able to "eject" antibiotics from the bacterial cell before they have a chance to exert any effect. Finally, the antibiotic target site within the bacteria can be altered. In this situation, when an antibiotic enters the bacterial cell it must bind to its intended target in order to have an effect on the bacteria. If the target within the bacteria has been changed to make this binding impossible, the bacteria will be resistant to the medicine’s effects.\n\nUnderlying the phenotypic mechanisms of antibiotic resistance are the genetics of antibiotic resistance. Bacteria, like other living organisms, possess DNA that codes for the proteins and enzymes it requires for survival. Changes to the DNA can result in alterations in the final proteins or enzymes, which in turn can lead to antibiotic resistance. A common genetic mechanism for the development of antibiotic resistance is the acquisition of tiny fragments of DNA known as plasmids or transposons. Transposons may code for a specific antibiotic-inactivating enzyme, which, when produced by the bacteria, destroys an incoming antibiotic before it has an opportunity to work. These tiny fragments may be passed directly from one bacterium to another by a process known as conjugation. Alternatively, small viruses may attack certain bacteria and inject DNA fragments by a process known as transduction. \nAnother genetic mechanism of antibiotic resistance is the acquisition and accumulation of resistance genes from neighboring bacteria through a process known as transformation. A good example of thi
558098
Adverse drug reactions\nCommon adverse drug reactions (ADRs) for the penicillins include: diarrhea, nausea, rash, urticaria, superinfection (including candidiasis). (Rossi, 2004)\n\nInfrequent ADRs include: fever, vomiting, erythema, dermatitis, angioedema, pseudomembranous colitis. (Rossi, 2004)\n\nPain and inflammation at the injection site is also common for parenterally-administered benzathine penicillin, benzylpenicillin, and to a lesser extent procaine penicillin.\n\nAllergy/hypersensitivity\nAllergic reactions to any β-lactam antibiotic may occur in up to 10% of patients receiving that agent. Anaphylaxis will occur in approximately 0.01% of patients. (Rossi, 2004) There is perhaps a 5-10% cross-sensitivity between penicillin-derivatives, cephalosporins and carbapenems; but this figure has been challenged by various investigators.\n\nNevertheless, the risk of cross-reactivity is sufficient to warrant the contraindication of all β-lactam antibiotics in patients with a history of severe allergic reactions (urticaria, anaphylaxis, interstitial nephritis) to any β-lactam antibiotic.\n\nHope I helped! ;)\nxxx
4271
Antibiotics are a valuable tool for fighting bacterial infections which persistantly do not resolve with your body's own Immune System.\n\nAntibacterial products have been touted to reduce infection from exposure to things you touch, wear, etc.  This is valuable for some people with compromised immune systems, but the normal healthy person really has no need for such products.\n\nIn fact, the use of those products and antibiotics are creating stronger more resistant bacteria in our environment.  With stronger more resistant bacteria comes the risk of NOT being able to get rid of an infection when one occurs.  \n\nExamples of resistant bacteria are MRSA and VRE.  These are very difficult infections to fight BECAUSE of their resistance.\n\nSo, to recap, most of the time exposure to bacteria will actually increase your immune systems ability to FIGHT that bacteria later and using too many products to kill bacteria can actually, in the end, hurt us.