Part II
-Antibiotics
-Antifungals
1)-Antibiotic
An antibiotic is a drug that kills or slows the growth of bacteria. Antibiotics are one class of "antimicrobials", a larger group which also includes anti-viral, anti-fungal, and anti-parasitic drugs. They are relatively harmless to the host, and therefore can be used to treat infections. The term originally described only those formulations derived from living organisms, but is now applied also to synthetic antimicrobials, such as the sulfonamides. Antibiotics are small molecules with a molecular weight less than 2000 and they are not enzymes.
Unlike previous treatments for infections, which included poisons such as strychnine, antibiotics were labelled "magic bullets": drugs which targeted disease without harming the host. Antibiotics are not effective in viral, fungal and other nonbacterial infections, and individual antibiotics vary widely in their effectiveness on various types of bacteria. Some specific antibiotics (called "narrow-spectrum antibiotics") target either gram-negative or gram-positive bacteria, and others are more wide-spectrum antibiotics. The effectiveness of individual antibiotics varies with the location of the infection and the ability of the antibiotic to reach this site. Oral antibiotics are the simplest approach when effective, with intravenous antibiotics reserved for more serious cases. Antibiotics may sometimes be administered topically, as with eyedrops or ointments.
Classes
There are many way to classify antibiotics.
1)-One such classification is by chemical structure:
- Aminoglycosides
- Amikacin
- Dibekacin
- Gentamicin
- Kanamycin
- Neomycin
- Netilmicin
- Paromomycin
- Sisomycin
- Streptomycin
- Tobramycin
- Beta-lactam ring antibiotics
- Carbapenems
- Cephalosporins and cephamycins
- Monocyclic beta-lactams
- Penicillins
- Glycopeptide antibiotics
- Oxazolidinones
- Linezolid
- Quinupristin/dalfopristin
- Polyketides
- Polymyxins
- Quinolones (fluoroquinolones)
- Nalidixic acid
- Ciprofloxacin (Cipro)
- Ofloxacin
- Norfloxacin (Norflox)
- Levofloxacin (Levaquin)
- Trovafloxacin (Trovan)
- Streptogramins
- Sulfonamides
- Other important antibiotics:
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