Know more about quinolones

1. QUINOLONES
By- Shehnaz khan
Bsc nursing 2nd year III semester

2. Introduction
• These are synthetic antimicrobials primarily active against gram negative
bacteria.
• They act as inhibiting DNA replication.

3. Mechanism Of Action
• They block bacterial DNA
synthesis via way of means of
inhibiting bacterial topoisomerase
(Ⅱ DNA gyrase) and
topoisomerase Ⅳ.
• Inhibition of DNA gyrase prevents
the rest of definitely supercoiled
DNA this is required for ordinary
transcription and replication.

5. Mechanism Of Action
1. Quinolones
2. Inhibit DNA gyrase
3. Inhibit negative super coiling of DNA
4. Inhibit relaxation of DNA
5. Inhibit separation of DNA fragments
6. Inhibit DNA replication
7. Destroy genetic material of bacteria
8. Destroy bacteria

7. Classification
Of
Quinolones

8. Nalidixic Acid
• The 1st generation of the quinolones begins with Nalidixic acid in 1962 for
the treatment of Urinary Tract Infections in humans.
• Bactericidal agent against gram negative organism like E. coli, Shigella ,
Proteus and Klebsiella.

9. Fluoroquinolones
• Fluoroquinolones are synthetic fluorinated analogue in nalidixic acid.
• They are divided into two groups , based on antimicrobial spectrum and
pharmacology –
• Old group – ciprofloxacin, norfloxacin and ofloxacin.
• New group – gemifloxacin , levofloxacin and moxifloxacin.

10. Uses Of Quinolones
1. Nalidixic acid is only second-line drug treating urinary infection with gram-
negative bacilli (Bacillus coli, Bacillus proteus , etc).
2. Pipemidic acid is not only used treating infection of urinary tract but also
treating intestinal and biliary tract infection.

11. Uses Of Fluoroquinolones
• Fluoroquinolones are extensively used treating general infection.
1. Urinary tract infections
2. Intestinal and biliary tract infections
3. Tuberculosis
4. Bone, joint and in intra-abdominal
5. Respiratory tract infections

12. Contraindication
• Children less than 18 years old
• pregnant or nursing women.
• A patient has epilepsy, QT prolongation, pre-existing CNS lesions, or CNS
inflammation, or
• the patient has suffered a stroke
• They are best avoided in the athlete population

13. DOSAGE
• Oral doses in adults are –
• 200–400 mg every 12 hours for ofloxacin.
• 400 mg every 12 hours for norfloxacin and pefloxacin.
• 250–750 mg every 12 hours for ciprofloxacin.
• 500-750 mg once daily for levofloxacin .

14. Adverse Effects
• The most frequent side-effects are
• Gastrointestinal reactions (nausea, dyspepsia, vomiting) and
• CNS reactions such as dizziness, insomnia and headache
• Risk of tendonitis and tendon rupture.

15. Nursing Responsibility
• Assess for hypersensitivity yo perticular Fluoroquinolones.
• Culture and sensitivity test sample to be collected.
• Assess for renal disease, pregnancy and hepatic disease.
• Monitor all allergic reactions.
• Intake and output monitoring.
• Advice patient to take plenty of water to prevent crystallization in kidneys.