Fluoroquinolones include the following :

Ciprofloxacin, Norfloxacin, Lomefloxacin, Ofloxacin, Pefloxacin, Enoxacin

Refer Ciprofloxacin

Interacting drugs- Fluroquinolones -summary

+ Ciprofloxacin
 
Sucralfate  +  Quinolones
  bioavailability of  quinolones decreased . Administering the
  quinolones > 2 hours    before sucralfate may eliminate the interaction.

Ciprofloxacin +

Betablockers 
 bioavailability of betablockers metabolised by cytochrome P-450
  increased

+ Fluoroquinolones +Antacids /Didanosine/Iron salts/Sucralfate / Zinc salts/ or + Fluoroquinolones

   interference with GI absorption of the fluoroquinolones resulting in
   decreased serum  levels. Avoid simulataneous use. Administer
   antacids 2 to 4 hours before or after  the fluoroquinolones  

Antineoplastic  agents + Fluoroquinolones
 fluoroquinolnes serum levels decreased    

Azlocillin   +  Ciprofloxacin 
 clearance of ciprofloxacin is decreased possibly increasing its pharmacologic
  effects. This combination  beneficial for some serious gram-negative
  infections, although it is not known if toxicity also increases.

Bismuth sub  salicylate +  Enoxacin  
enoxacin bioavailability is decreased when bismuth sub salicylate is given
 before or 60 minutes after enoxacin. Avoid concurrent use.     

Cimetide   +  Fluroquinolones 
cimetidine interfere with the elimination of the fluoroquinolones

Nitrofurantoin + Norfloxacin
antibacterial effect of norfloxacin inthe urinary tract  antagonised

Probenecid   +  Fluoroquinolones 
 ciprofloxacin renal clearance is reduced 50% and its serum concentration
  is increased 50% , diminished norfloxacin and lomefloxacin urinary excretion
 has  occurred.
 
Ciprofloxacin/ Enoxacin / Norfloxacin   + Caffeine  
 total body clearance is reduced, possibly resulting in increased  pharmacologic
 effects. Ofloxacin and lomefloxacin do not appear to affect caffeine. Enoxacin
  plasm levels were also 20% higher.
 
Ciprofloxacin / Norfloxacin + Cyclosporine
  the nephrotoxic effect of cyclosporine  increased

Enoxacin  +  Digoxin
 digoxin serum levels  increased . Monitor digoxin levels.          

Ciprofloxacin +  Hydantoin
phenytoin serum levels  reduced , producing a decrease in therapeutic   effects
    
Fluroquinolones +  Anticoagulants
 the effects of the anticoagulant may be increased. Monitor prothrombin 
 time

Fluroquinolones +  Cyclosporine
 nephrotoxic effects  increased,. Closely monitor renal function.
  Conflicting data exist

CIPROFLOXACIN-

GU- Acidosis, interstital nephritis, nephritis, renal failure, polyuria, urinary retention, urethral bleeding, vaginal candidiasis, renal calculi.

Cardiovascular- angina pectoris, atrial flutter, cardiopulmonary arrest, cerebral thrombosis, myocardial infarction,ventricular ectopy, postural hypotensuion,

Respiratory- bronchodpasm, dyspnea, epitaxis, hemoptysis, hiccoughs, larryngeal/pulmonary edema, pulmonary embolism

Special senses- bad taste in mouth, eye pain, tinnitus, nystagmus

Miscellaneous- restlessness, oral/cutaneous candidiasis, intestinal perforation, GI bleeding, nightmares irritability, tremor, ataxia, anorexia, urticaria, flushing, hyperpigmentation, erythema nodosum, hepatic necrosis, exacerbation of myasthenia gravis, agranulocytosis, cholestastic jaundice

NORFLOXACIN-

Miscellaneous- erythema, myoclonus (rare) erythema multiforme, hepatitis, pancreatitis, stomatitis, arthalgia

OFLOXACIN-

GU- vaginal discharge, genital pruritus, burning/irritation/pain of female genitalia, dysmenorrhea, metrorrhagia, urinary frequency/pain.

Cardiovascular- chest pain, vasodilation Respiratory- cough, rhinorrhea

Special senses- Dysgeusia, photophobia

CNS- sleep disorders, nervousness, anxiety, cognitive change, dream abnormality, euphoria, vertigo.

Miscellaneous- decreased appetite, arthalgia, asthenia, diaphoresis, myalgia, thirst, vasculitis, weight loss.

LEMOFLOXACIN-

GU- dysuria, hematuria, strangury, micturation, anuria, leukorrkhea, intermenstrual bleeding, perineal pasin, vaginal moniliasis, orchitis, epididymitis

Cardiovascular- hypotension, tachycardia, bradycardia, arrhythmias, extrasystoles, cyanosis, cardiac failure, angina pectoris, myocardial infarction, pulmonary embolism, cerbrovascular disorder, cardiomyopathy, phlebitis

Respiratory- dyspnea, respiratory infection, epistaxis, respiratory disorder, bronchospasm, cough, increased sputum, stridor

CNS- coma, hyperkinesia, tremor, vertigo, nervousness, anorexia, anxiety, agitation, increased appetite, depersonalization, paroniria.

GI- GI inflammation,/bleeding, dysphagia, tongue discoloration, bad taste Special senses- earache, tinnitus, conjuntivitis, eye pain.

Dermatologic- urticaria, eczema, skin exfoliation, skin disorder

Miscellaneous- flushing, increased sweating, back/chest pain, asthenia, facial edema,influenza-like symptoms,decreased heat tolerance, purpura, lymphadenopathy, increased fibronysis, thirst, gout, hypoglycemia, leg cramps, artharlgia, myalgia, abnormalities of urine specific gravity or serum electrolytes

ENOXACIN

GI- anorexia, bloody stools, gastritis, stomatitis

CNS- nervousness, anxiety, tremor, agitation, myoclonus, depersonalization, hypertonia.

Dermatologic- urticaria, hyperhidrosis, mycotic infectoion, erythema multiforme,

Special senses- verigo, unusual taste, tinnitus, conjuntivitis.

Respiratory- dyspnea, cough, epistaxis

GU- vaginal monoliasis, urinary incontinence, renalfailure

Miscellaneous- asthena, back/chest pain, myalgia, arthralgia, tacchycardia, vasodilation, purpura

Children below 12years and growing adolescencts,except where benefits exceed risks. Pregnancy, lactation, hypersens.

Special precautions:

Epilepsy, severe renal dysfunction, history of convulsive disorders.

Patients should be well hydrated. G6PD defects.

Monitoring- periodic assesment of organ functions, including renal, hepatic and hematopoetic is advisable during prolonged therapy

Opthalmologic abnormalities- including cataracts and multiple punctate lenticular opacities, hav occurred during therapy with some quinolones

Crystalluria- needleshaped crystals were found in the urine of some volunteers who received either placebo or 800 or 160 mg norfloxacin. While crystalluria is not expected to occur under usual conditions with 400mg twice daily, do not exceed the dose. Patientshould drinl sufficient fluids to ensure proper hydration and adequate urinary output.

Photoxicity- reactions moderate to severe have occured in patients who are exposed to direct sunlight while receiving some drugs in this class.

Superinfection: Use of antibiotics especially over a prolonged or repeated therapy may result in bacterial or fungal overgrowth of susecptible organisms. such overgrowth may lead to secondary infection. Take appropiate measures if this occurs.

Drug/Food interations- Food may decrease the absorption of norfloxacin. Food delays absorption of ciprofloxacin, resulting in peak concentrations that are closer to 2 hours after dosing rather than 1 hour. Food delays the rate of absorption of lomefloxacin( time to reach maximum plasma concentration delayed by 41%, and minimum concentration decreased by 18%.)

Warnings

Photosensitivity- moderate to severe phototoxic reactions have ocurred in patients exposed to direct sunlight or indirect sunlight or to artificial ultraviolet light during or following treatment with lomefloxacin

Convulsion- increased intracranial pressure and toxic psychosis have occured

. CNS stimulation may also occur which may lead to tremor, restlessness, lightheadness, confusion and hallucinations. Use with caution in patients with known CNS disorders.

Syphillis- Ofloxacin and enoxacin are not effective for syphilis. High doses of antimicrobial agents for short periods of time to treat gonorrhea may mask or delay symptoms of incubating syphilis Patients treated with ofloxacin and enoxacin should have a follow- up serological test after 3 months.

Chronic bronchitis due to Staph pneumoniae- lomefloxacin is not indicated for the empiric treatment of acute bacterial exacerbation of chronic bronchitis when it is probable that S pneumoniae is the causative organism since it exhibits in vitro resistence to lo there is a predominance of gram negative and gram positive organisms.

Hypersensitivity- reactions serious and occasionally fatal have occured in patients receiving quinolone therapy, some following the first dose. Some reactions were accompanied by cardiovascular collapse, loss of consciousness,tingling,pharyngeal or facial edema, dyspnea, urticaria and itching

Pseudonomembranous colitis- has been reported when nearly all antibacterial agents including fluoroquinolone and may range from mild to life threatening in severitry. Therefore, it is important to consider this diagnosis in patients who present with diarrhea subsequent to administration of antibacterial agents.

Renal function impairment- alteration in dosage regimen is necessary.

Fertility impairment- decreased spermatogenesis and subsequent decreased fertility occured in animals given doses that produced plasma levels 3 times higher than those in humans in recommended dosage.

Elderly- norfloxacin is eliminated slowly because of decreased renal funtion., absorption appears unaffected.

The apparent half life of ofloxacin is 6 to 8 hours.

Lomefloxacin plasma clearance was reduced by about 25% and AUC was increased by 33% in elderly, which may be due to reduced renal function.

Enoxacin plasma concentrations are 50% higher in the elderly than in younger adults.

Pregnancy- Use during pregnancy only if the potential benefits justifies the potential risk to the fetus.

Lactation- because of the potential serious adverse reactions in nursing infants, decide whether to discontinue nursing or discontinue the drug, taking into consideration the importance of the drug to the mother.

Children- Do not use in children. Safety and efficacy of lomefloxacin, enoxacin, ofloxacin in children < 18 years of age have not been established

Approved by FDA in 1987

Infections of urinary tract, respiratory tract,

infections of bone & joints,skin & skin structure,

diarrhoea.

Dosage:

Mild to moderate infections- 500mg- 400mg I.V. divided 12 hourly

Severe/complicated infections - 1000mg- 800mg I.V. divided 12 hourly

Recommended maximum- 1500mg- divided 12 hourly

Administer I.V.infusion over 60 minutes. Slow infusion of dilute solutions into a lage vein will minimise patient discomfort and reduce risk of venous irritation.

Stability: Stable upto 14 days at refrigerated or room temp(5C to 25C;41F to 77F).,when diluted with 0.9% Nacl inl.USP or 5% dextrose inj,USP.. Protect from freezing.

. Overdosage- Symptoms

One patient developed oliguric acute renal failure following ingestion of 21g of ciprofloxacin. The patient responded to prednisolone therapy

Treatment

1. Empty the stomach by inducing vomiting or by gastric lavage

2. Observe patient carefully and give supportive treatment

3. Maintain adequate hydration.

4. Hemodialysis or peritoneal dialysis may aid in the removal of ciprofloxacin,particularly if renal function is compromised.

5. Ofloxacin, enoxacin, norfloxacin, and lomefloxacin are not efficiently removed by dialysis. 

Missed dose-

1. If you miss a dose of this medicine, take it as soon as possible

 2. However, if it is almost time for next dose, skip the missed dose and go back to your regular dosing schedule.

3. Do not double doses.

1. Drink fliuds liberally

2. Do not take antacids containing magnesium or aluminium or products containing iron or zinc simultaneously or within 4 before or 2 hours after dosing.

3. May cause dizziness or lightheadedness. Observe caution while driving or performing other tasks requiring alertness,co-ordination or physical dexterity.

4. CNS stimulation may occur (eg tremor, restlessness, confusion. Use with caution in patients predisposed to seizures or with CNS disorders.

5. Allergies- Tell your doctor if you have ever had any unusual or allergic reactions to fluoroquinolones or any related medicines such as cinoxacin or nalidixic acid. Also tell your doctor if your are allergic to any other substances such as foods, preservatives or dyes

 6. Pregnancy- use not recommended during pregnancy

 7.Breast feeding- fluoroquinolones have been reported to cause bone development problems in young animals.

8.Children- use not recommended for infants or children since fluoroquinolones have been shown to cause bone development problems in young animals

 9. Elderly- these medicines have been tested in effective and have not shown to cause different problems in elderly people than in younger adults.

10. Other medicines-Tell your doctor if you are taking other medicines- Aminophylline or Oxytriphylline or Theophylline - enoxacin ,ciprofloxacin and norfloxacin may increase the chance of side effects of aminophylline,

 11. Other medical problems- presence of other medical problems may affect the use of this medicine- Brain or spinal cord disease including hardening of arteries in the brain or epilepsy or other seizures- fluroquinolones may cause nervous system side effects

 12. Missed dose- If you miss a dose of this medicine take it as soon as possible. However if it is almost time for your next dose go back to your regular dosing schedule. Do not double dose

Food may decrease the absorption of norfloxacin.

Food delays absorption of ciprofloxacin, resulting in peak concentrations that are closer to 2 hours after dosing rather than 1 hour.

Food delays the rate of absorption of lomefloxacin( time to reach maximum plasma concentration delayed by 41%, and minimum concentration decreased by 18%.)

Pregnancy

Do not use in pregnant women. There are no adequate and well controlled studies in pregnant women. Use during pregnancy only if the potential benefit justifies the potential risks to the fetus.

Lacation:

Norfloxacin was not detected in breast milk following administration of 20mg to nursing mothers; however this was a low dose.

Ciprofloxacin is excreted in breast milk,however the amount ingested by the infant appears low.

It is known whether lomefloxacin or enoxacin are excreted in breast milk. Because of the potential for serious adverse reactions in nursing infants, decide whether to discontinue nursing or discontinue the drug, taking into consideration the importance of the drug to the mother.

Children:

Do not use in children. Safety and efficacy of lomefloxacin, enoxacin and ofloxacin in children below 18 years of age have not been established.