Anaphylaxis is a hypersensitive reaction due to contact through allergens. These allergens induce an immediate immune response that is life threatening in most occasions. Anaphylactic reactions produce various clinical symptoms such as urticaria, respiratory congestion and gastrointestinal disturbances. Anaphylactic response is caused by certain type of compounds which may include proteins, pollen, venom, hormones and also some food extracts. The immunoglobulin E or IgE is responsible for the onset of anaphylactic reaction when exposed to an allergen.
Mechanism of anaphylactic reaction
A series of reactions take place in the body when anaphylaxis is triggered. The IgE which has a half-life of two days, binds to the fragment crystallizable or FC receptor part of the basophils and mast cells. This process is activated when the person comes in contact with an allergen which in turn mediates cellular de granulation and their release of biogenic amines such as histamine and serotonin. The effects of these biogenic amines may include the smooth muscles which generally constrict at the bronchiolar region and broncho capillary venules. It also causes the arteriole dilation.
Anaphylactic responses are of different types and are associated with allergen sources of different kinds such as pollen, food, insects and also some drugs. It happens because of the antigen contact to which the patient had been previously exposed. This type of antigen is also called an allergen. Systemic anaphylaxis is a serious condition in which the mast cells of the connective tissue become activated resulting in dangerous effects such as airway obstruction, swelling of the epiglottis and ultimately suffocation. Systemic anaphylaxis proceeds into another condition called anaphylactic shock which happens because of suffocation induced by the respective allergen. In addition to these, anaphylaxis may also result because of extreme physical exercise. This condition is also called exercise induced urticaria. Allergies to food like eggs and milk are common among infants. Other than these, underlying conditions such as hay fever, asthma and eczema may also induce anaphylaxis if untreated.
Anaphylactic shock is widely reported in people after consuming foods such as peanuts and Brazil nuts. Such food products induce the anaphylactic reaction in an instant causing severe discomfort and sometimes death. Many people also experience anaphylactic reactions because of penicillin administration. Some reactions of anaphylaxis also include excess production of mucous in the mouth, nose and throat. Atopic patients are highly susceptible to anaphylaxis. Patients having an underlying atopic condition produce high amount of IgE antibodies and hence they must be monitored carefully.
Diagnosis of Anaphylaxis
Anaphylactic reaction is diagnosed based on clinical symptoms such as skin rash (insect bites), hoarse voice, chest congestion, breathing difficulty, diarrhea, vomiting and abdominal cramps. Identification of the source is the predominant factor in the diagnosis of anaphylactic reactions. Thorough examination of the cause with immediate life saving measures must be done. Anaphylaxis can be fatal if not managed properly.
Avoid foods that induce the condition. In the case of anaphylactic reaction, medical attention must be sought immediately. Oral medications such as Benadryl or diphenhydramine are given. EpiPen or injectable epinephrine is the drug of choice to control the anaphylactic reaction. Intravenous antihistamine drugs and oral steroids are given for a period of time to prevent the reoccurrence of the anaphylactic reactions.
An Immunologist can be described as a medical specialist trained to prevent, diagnose, manage and treat diseases that result from abnormalities of the immune system. Immunologists are highly qualified and trained to treat immune system disorders such as allergies, asthma, inherited immunodeficiency diseases and autoimmune diseases. Clinical immunologists and allergy specialists undergo similar training as with any other medical specialists. After completion of four years of premedical education at a college or university, they receive at least four years of medical school education. After receiving general training in internal medicine, they receive additional training in immunology and allergy areas. Immunologists are involved in a gamut of work areas, in hospitals, private practice, diagnostic immunology laboratories, research centers and industrial houses. The medical immunologist or allergy specialist primarily identifies and treats the diseases that result from abnormalities of the immune system.
List of general Antibiotics
Antibiotics are primarily used to treat bacterial infections. They may have secondary uses - treatment of the Syndrome of Inappropriate Antidiuretic Hormone (SIADH) secretion with Declomycin. Some antibiotics are also used to prevent infection (antibiotic prophylaxis) before any surgery or in the case of weakened immune systems. There was a study which indicated that about 300 million prescriptions for antibiotics are issued every year in the US alone and the wide spread use or abuse of the antibiotics is a serious issue. For example, an antibiotic can seriously deplete the normal intestinal micro flora which can result in vaginal yeast infection in susceptible women. Indiscriminate use of antibiotics can bring about increased incidences of Streptococcal disease in children apart from enhanced drug resistance.
Antibiotics Classification: Antibiotics are classified under many categories. Commonly they are grouped based on chemical structure and Antibiotics within the same class exhibit similar kind of effectiveness, allergic potential and toxicity. The exhaustive list below also contains drug allergy or other reactions possible for susceptible individuals as appropriate under each class.
Other types of classification:
Bacterial Spectrum: Broad Spectrum Antibiotics are capable of targeting many types of bacteria while narrow spectrum antibiotics target specifically a single class of bacteria. It is generally preferable to use a specific antibiotic for the specific class of bacteria.
Type of Activity: Bactericidal drugs are intended to kill bacteria while bacteriostatic drugs are intended to inhibit the growth of bacteria.
Broad Spectrum Antibiotics: According to a Swiss Study, this class of Antibiotics which act against Gram+ and Gram- bacteria is prone to misuse. Broad Spectrum Antibiotics - specifically the antipseudomonal agents (i.e. cefepime, ceftazidime, ciprofloxacin, imipenem, meropenem, piperacil lin/tazobactam) plus trovafloxacin were found to be misused.
The following list shows the generic names of common antibiotics prescribed and available under various trade names in the US. We have broadly classified them under the common 'family' names.
Broad Spectrum Penicillins / Amoxicillin
Penicillins - one of the oldest type of broad spectrum antibiotics, share common chemical structure with Cephalopsorins. They are classified as Beta-lactam antibiotics. Aminopenicillins such as Ampicillin and Amoxicillin have extended spectrum of action. Extended Spectrum Penicillins are effective against a broad range of bacteria including Pseudomonas Aeruginosa which affect patients with weakened immune systems.
Allergic reactions are common with Penicillins for susceptible individuals. Cephalosporins can cause seizures or affect the blood clotting time for susceptible patients.
Penicillins and Beta Lactamase Inhibitors
Cephalosporins, one of the largest classes of Antibiotics are used to treat a long list of bacterial infections from around the year 1950. The latest in this class, Ceftaroline is a new fifth generation Cephalosporin - a broad spectrum Antibiotics that shows promise against Gram + bacteria including Methicillin Resistant Staphylococcus Aureus (MRSA),Vancomycin Intermediate S.Aureus (VISA), Vancomycin Resistant S.Aureus (VRSA)and Heteroresistant VISA (hVISA).
Cephalosporin II Generation Antibiotics
Cephalosporin III Generation Antibiotics
Cephalosporin IV Generation Antibiotics
Fourth generation Cephalosporin antibiotics are effective in the treatment of Encephalitis and Meningitis as they cross the blood-brain barrier.
Cephalosporin V Generation Antibioticsor New Generation Cephalosporins - NGCs
The New Generation Cephalosporins show considerable efficacy against a host of bacteria - from MRSA to respiratory pathogens like Streptococcus Pneumoniae, Haemophilus Influenzae and Moraxella Catarrhalis.
β lactam antibacterial resistance: These fifth generation Cephalosporins inhibit the cell wall synthesis of Penicillin Binding Proteins (PBPs). For example, Ceftaroline's anti MRSA efficacy stems from its high affinity for the MRSA associated (Penicillin Binding Proteins)PBP2a. It may have affinity greater than 256 times over other β lactams.
Ceftaroline is effective against the following:
Gram Positive Bacteria which cause skin infections:
Methicillin Resistant Staphylococcus Aureus (MRSA) and resistant isolates
Gram Positive Bacteria which cause Community Acquired Bacterial Pneumonia (CABP):
Staphylococcus aureus(methicillin susceptible isolates)
Gram Negative Bacteria:
Macrolides and Lincosamines
Macrolide Antibiotics have macrocyclic lactone chemical structure. Erythromycin and the newer antibiotics belonging to this broad spectrum class - Azithromycin and Clarithromycin are widely used for their higher level of lung penetration. Erythromycin may rarely result in Myasthenia gravis while Azithromycin may rarely result in Angioedema (Patches of swelling of the skin, mucus membranes and internal organs), Anaphylaxis (hypersensitive reaction due to contact through allergens) or other allergic reactions.
Quinolones and Fluoroquinolones
Fluoroquinolones are synthetically manufactured broad spectrum Antibiotics. Lomefloxacin is reported to cause increased photosensitivity and in some cases may result in convulsion.
Beta lactam Antibiotics: Carbepenems
Aminoglycosides : These antibiotics are specifically used to target aerobic, Gram-negative bacteria. Generally useful against Pseudomonos, Acinetobacter and Enterobacter amongst others. Streptomycin is effective to control tuberculosis causing mycobacteria. Antibiotic treatment with Aminoglycosides often involves the use of another antibiotics for overall better synergetic effect.
Tetracyclines are not normally prescribed for children under the age of 8 due to the permanent tooth discoloration these drugs cause.
Rifampin also known as Rifampicin (Rifadin)
Many Antibiotics are available for external application on the skin which include:
Topical medications that act as Comedolytics as well as antibiotics:
Recommended Dosage : Antibiotics dosage is based on many factors:
Many antibiotics can be administered parenterally - either through Intravenous (IV) or Intra muscular (IM) injections.
You may find some typical usage instructions, dosage, contra indications and side effects - if any for some of the antibiotics listed above in these pages.
Antibiotics for Anaerobic infections
Anaerobes - the kind of bacteria which can not grow in the presence of oxygen, can infect deep wounds and internal organs - sometimes resulting in gangrene, botulism, tetanus and almost all dental infections.
Some common Anaerobic infections
Many antibiotics do not inhibit/control Anaerobes. But Chloramphenicol, Imipenem, Metronidazole, Clindamycin and Cefoxitin are effective against these bacteria.
New Antibiotics in pipeline: Pseudouridimycin (PUM) is a promising new Antibiotic which inhibits bacterial RNA polymerase (RNAP). What is more, PUM in the research shows its ability to act against drug resistant bacterial pathogens.
Bibliography / Reference
Collection of Pages - Last revised Date: September 20, 2018