Ethambutol

The mechanism of ethambutol (Myambutol) is not fully understood. This drug apparently suppresses RNA synthesis in susceptible bacteria, but it is not known how this occurs. Ethambutol is primarily effective against M. tuberculosis infections and is a secondary agent in the treatment of tuberculosis.61 Adverse effects associated with this drug include joint pain, nausea, skin rash and itching, and CNS abnormalities (dizziness, confusion, hallucinations). 

The exact mechanism of metronidazole (Flagyl, Proto-stat, others) is not fully understood. This drug appears to be incorporated into bacterial cells, where it undergoes chemical reduction. Apparently, the reduced 

Mupirocin (Bactroban) inhibits a specific enzyme responsible for tRNA synthesis in susceptible bacteria. This drug is used topically to treat skin infections caused by Staphylococcus aureus or Streptococcus pyogenes. Likewise, mupirocin can be administered by nasal spray to treat local colonization of S. aureus in the nasal mucosa. This idea may be especially helpful in preventing systemic infection in individuals such as health care workers who are exposed to an outbreak of resistant strains of S. aureus. Local/topical administration of this drug is well tolerated, although some irritation of the skin may occur during topical use, and cough and respiratory irritation can occur when mupirocin is administered by nasal spray. 

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Because they are similar, the aLkanolamines often can be used interchangeably. However, cost/perfomiance considerations generally dictate a best choice for specific appHcations. AMPD is manufactured in very low volumes for use as a reagent in certain medical diagnostic tests, although some is used in certain cosmetic products. 2-Ainino-1-butanol is used primarily as a taw material for the synthesis of ethambutol [74-55-5] an antituberculosis dmg. The first step in the synthesis of this dmg is the resolution of AB into its optical isomers because only (i)-2-amino-l-butanol, [5856-62-2] is utilized in this synthesis. 

The initial phase must contain three or more of the following drugp isoniazid, rifampin, and pyrazin-amide, along with either ethambutol or streptomycin. The CDC recommends treatment to begin as soon as possible after the diagnosis of tuberculosis. The treatment recommendation regimen is for the administration of rifampin, isoniazid, and pyrazinamide for a minimum of 2 months (8 weeks), followed by rifampin and isoniazid for 4 months (16 weeks) in areas with a low incidence of tuberculosis. In areas of high incidence of tuberculosis, the CDC recommends the addition of streptomycin or ethambutol for the first 2 months. 

This chapter will discuss the following primary aiititubercular drugp ethambutol, isoniazid, pyrazin-amide, rifampin, and streptomycin. Other primary and secondary drugp are listed in the Summary Drug Table Aiititubercular Drugp. 

Optic neuritis (a decrease in visual acuity and changes in color perception), which appears to be related to the dose given and die duration of treatment, has occurred in some patients receiving ethambutol. Usually, tiiis adverse reaction disappears when the drug is discontinued. Other adverse reactions are dermatitis, pruritus, anaphylactoid reactions (unusual or exaggerated allergic reactions), joint pain, anorexia, nausea, and vomiting. 

ETHAMBUTOL The nurse monitors for any changes in visual acuity and promptiy reports any visual changes to tlie primary health care provider. Vision changes are usually reversible if tlie drug is discontinued as soon as symptoms appear. The patient may need assistance with ambulation if visual disturbances occur. Psychic disturbances may occur. If die patient appears depressed, withdrawn, noncommunicative, or has otiier personality changes, the nurse must report the problem to the primary health care provider. 

Ethambutol Take this drug once a day at the same time each day. If a dose is missed, do not double the dose the next day. Notify the primary health care provider of any changes in vision or the occurrence of a skin rash. 

Which of the following is a dose-related adverse reaction to ethambutol ... 

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