Aminoglycosides drugs

Medications Avoid concurrent use of potentially nephrotoxic drugs (e.g., nonsteroidal antiinflammatory drugs, aminoglycosides) A-2... 

Drug Aminoglycoside-phospolipid (molar ratio)9 Energy of interaction6 Phospholipase A1 inhibition (%)c... 

Use of suboptimal doses of drugs in serious disease, sacrificing efficacy for avoidance of serious adverse effects, has been documented. It particularly affects drugs of low therapeutic index (see Index), i.e. where the effective and toxic dose ranges are close, or even overlap, e.g. heparin, anticancer drugs, aminoglycoside antimicrobials. In these cases dose adjustment to obtain maximum benefit with minimum risk requires both knowledge and attentiveness. 

An additive neplirotoxicity develops when pentamidine isetliionate is administered witli otlier nephrotoxic drugs (, aminoglycosides, vancomycin, or amphotericin B). An additive bone marrow depression occurs when tlie drug is administered witli antineoplastic drugs or when tlie jiatieiit lias received radiation tlierapy recently. 

Streptomycin is the drug of choice for treatment of plague and tularemia and has important adjunctive value in tuberculosis. Gentamicin (plus tetracycline) is usually preferred in brucellosis, but streptomycin is a backup drug. Aminoglycosides have minimal activity in Lyme disease, which is usually treated with either doxycycUne or amoxicillin. The answer is (C). 

Figure 7.5 Staph, and Strep, are protected by a crosslmked glycoprotein ivall. Penicillin, cephalosporins, imipenem, aztreonam and vancomycin prevent construction/repair of the wall. In the presence of these drugs, aminoglycosides readily penetrate the damaged wall. Thus combinations such as ampicillin/ gentamicin and tobramycinP imentin act synergistically.

Second-line drugs Aminoglycosides Polypeptides Fluoroquinolones Thioamides Cycloserine p-Aminosalicylic acid... 

The preferred substrates of acetyltransferases are amino-groups of antibiotics, like chloramphenicol, strepto-gramin derivatives, and the various aminoglycosides. The modification is believed to block a functional group involved in the drug-target-interaction. All acetyltransferases use acetyl-coenzyme A as cofactor. 

Patomomycin This oral aminoglycoside was first shown to be effective as a topical treatment for cutaneous leishmaniasis, and later as a parenteral drug against visceral leishmaniasis. Phase III clinical trials were completed in 2005 in India, 15 years after the potential of this component for treating viscer al leishmaniasis was discovered. It is currently not registered for this use. 

Drug resistance in the defined sense, however, is not always the reason for treatment failures. The formation of biofilms may be as well regarded as a resistance mechanism. Cells within such a film withstand the antibiotic treatment. Some antibiotics (e.g. the aminoglycoside tobramycin) penetrate only slowly into the film. A further explanation is the existence of cells living in a non-growing, protected phenotypic state. 

Smith CA, Baker EN (2002) Aminoglycoside antibiotic resistance by enzymatic deactivation. Curr Drug Targets Infect Disord 2 143-160... 

Ototoxicity describes a harmful effect on the inner ear, especially the sensory cells in the cochlea and the vestibular organ. Aminoglycosides are an example of drugs with ototoxic side effects. 

Discuss the uses, general drug action, contraindications, precautions, interactions, and adverse reactions of the fluoroquinolones and aminoglycosides. 

Additional adverse reactions seen with administration of the aminoglycosides may include nausea, vomiting, anorexia, rash, and urticaria When these drugs are given, individual drug references, such as the package insert, should be consulted for more specific adverse reactions. 

Like the other anti-infectives, bacterial or fungal superinfections and pseudomembranous colitis (see Chap. 7) may occur with the use of these drags. The administration of the aminoglycosides may result in a hypersensitivity reaction, which can range from mild to severe and in some cases can be life threatening. Mild hypersensitivity reactions may only require discontinuing the drug, whereas the more serious reactions require immediate treatment. 

The primary health care provider may order culture and sensitivity tests, and the culture is obtained before the first dose of the drug is given. When an aminoglycoside is to be given, laboratory tests such as renal and hepatic function tests, complete blood count, and urinalysis also may be ordered. 

D Disturbed Sensory Perception Auditory related to adverse drug readions ot the aminoglycosides... 

Monitoring and Managing Adverse Drug Reactions A variety of adverse reactions can be seen with the administration of the fluoroquinolones or aminoglycosides. The nurse observes die patient, especially during the first 48 hours of tiierapy. It is important to report the occurrence of any adverse reaction to the primary health care provider before die next dose of the drug is duei If a serious adverse reaction such as a hypersensitivity reaction, respiratory difficulty, severe diarrhea, or a decided drop in blood pressure occurs, the nurse contacts die primary health care provider immediately. 

Monitoring and Managing Adverse Drug Reactions Aminoglycosides... 

Spectinomycin (Trobicin) is chemically related to but different from the aminoglycosides (see Chap. 10). This drug exerts its action by interfering with bacterial protein synthesis. Spectinomycin is used for the treatment of gonorrhea... 

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