Tags: Tequin

Specific Anti-Infective Agents

Clinicians should be familiar with the general classes of antibiotics, their mechanisms of action, and their major toxicities. The differences between the specific antibiotics in each class can be subtle, often requiring the expertise of an infectious disease specialist to design the optimal anti-infective regimen. The general internist or physician-in-training should not attempt to memorize all the facts outlined here, but rather should read the pages that follow as an overview of anti-infectives. The chemistry, mechanisms of action, major toxicities, spectrum of activity, treatment indications, pharmacokinetics, dosing regimens, and cost are reviewed.

Community-Acquired Pneumonia: Current Therapies

Many highly effective agents are available for the treatment of bacterial community-acquired pneumonia (community-acquired pneumonia) and other community-acquire respiratory tract infections (RTIs). Currently marketed antibiotics for community-acquired pneumonia demonstrate similar efficacy rates in clinical trials, and these agents have generally achieved clinical symptom resolution in 85-95% of trial participants.

Gatifloxacin (Gatiflo, Tequin and Zymar)

Gatifloxacin has a broad spectrum of activity similar to activity observed in other third-generation fiuoroquinolones. The agent is well absorbed following oral administration (almost 100% bioavailability), and its pharmacodynamic and pharmacokinetic properties (e.g., high volume of distribution, long elimination half-life) allow once-daily administration.


Gemifloxacin, as a member of the fluoroquinolone class, acts by inhibiting bacterial topoisomerase IV and DNA gyrase. These enzymes are required for DNA replication, transcription, repair, and recombination.


Fluoroquinolones are broad-spectrum antibacterials that have experienced an upsurge in use in recent years. Because of their broad-spectrum activity, high efficacy, favorable dosing, and availability in oral and IV form, these agents are indicated for a range of bacterial infections, including respiratory, GI, and urinary tract infections. Earlier generations of fluoroquinolones (e.g., ofloxacin) had limited activity against some respiratory pathogens, such as S. pneumoniae. However, more recent fluoroquinolone agents (so-called third-generation agents or the “respiratory fluoroquinolones”) are active against a broad spectrum of gram-positive and gram-negative bacteria, including atypical organisms.

Acute Exacerbations of Chronic Bronchitis: Current therapies

TABLE: Pharmacological Management of Underlying Disease During an Acute Exacerbation of Chronic Bronchitis summarizes the general pharmacological agents and classes used to manage acute exacerbations of chronic bronchitis. The primary therapies used in acute exacerbations of chronic bronchitis treat the causative infection (antibiotics), relieve symptoms (bronchodilators), and treat the underlying inflammation (corticosteroids). TABLE: Current Therapies Used for Acute Exacerbations of Chronic Bronchitis summarizes the leading antibiotic therapies used to treat the infection.