Ocular Pharm: L12: Other Oral and IV Drugs: Fluoroquinolones and CAIs Flashcards
Evolution of Fluoroquinolones
- First Gen (1)
- Second Gen (3)
- Third Gen (1)
- 4th Gen (2)
- What improves in Later generations?
- Nalidixic Acid
- Ciprofloxacin, Ofloxacin, Norfloxacin
- Levofloxacin*
- Gemifloxacin, Moxifloxacin*
- Improved POTENCY, Increased broadness of Activity (more Gram +) and Safety in later generations
* = Most Frequently Used
Resistant Organisms
- Resistant Organisms have been found in what 4 CLASSES?
- Mechanisms of Resistance
a. PLASMID MEDIATED: What protein mutations?
b. Mutations in what 2 enzymes?
c. What’s impaired that causes resistance?
- a. MRSA, Pseudomonas, Enterococci, Coagulase-Negative Staphylococci
- a. Qnr Protein Mutations
b. in Gyrase and Topoisomerase
c. Impaired Entry and Enhanced Efflux of Drug
Pharmacokinetics
*Listen to lecture to see what we need to know…
Side Effects (1)
- What are the Most frequent side effects?
- What are the next most frequent?
- What other ones are possible?
- What are other ones?
- GI (Nausea and vomiting, anorexia)
- Nervous system (dizzy, hallucinations, delirium)
- Peripheral Neuropathy, Rash and other allergic issues, Phototoxicity RxNs, Drug fever, Arthropathy (cartilage erosions), Tendinopathy and Tendon Rupture.
- QT interval Prolonged and Arrhythmia, Transaminitis and Liver Failure, Hyper and Hypoglycemia (AVOID in DIABETICS), Hematologic,
RETINAL DETACHMENT (according to Canadian Study; However, Denmark Study said that Fluoroquinolones are not associated w/increased risk of Retinal Detachment)
Drug Interactions
- Reduced Absorption of what 5 things?
- Impaired Elimination of what?
- What may EXACERBATE CNS Effects?
- fluoro’s can INTERACT with DRUGS that prolong what?
- May effect Pharmacokinetics of what 2 drugs?
- Antacids, Vitamins w/Zinc, Ferrous Sulfate, and Didanosine
- of Methylxanthines
- NSAIDs
- that Prolong the QT interval
- of Cyclosporine and Warfarin
Issues w/Newer Agents
- Grepafloxacin: Why was it withdrawn?
- Trovafloxacin: Why was it withdrawn?
- Gatifloxacin: Why was it withdrawn?
- Gemifloxacin: What % of women under 40 develop a RASH when taking it for LONGER than SEVEN DAYS?
- Adverse Cardiac Events
- risk of Hepatic Toxicity
- Increased Frequency of Hypoglycemia and Hyperglycemia compared to other marketed Fluoroquinolones
- 14% *mainly avoid this by doing just a 5 day course of treatment
General Guidelines for Use
- What should be used for DEEP or SEVERE Ocular BACTERIAL INFECTIONS?
a. What other situation? - Why do we have to be careful when using Fluoroquinolones?
- Why do we have to be conservative in the use of these drugs?
- Oral or IV Fluoroquinolones.
a. or for bacterial infections that DONT RESPOND to OTHER ORAL TREATMENTS - they can cause serious side effects: (Avoid when CONTRAINDICATED (Arryhtmia’s). Monitor for Side Effects (liver function). Limit Duration of Use
- Due to resistance already starting to develop. (Use an older class of antibiotic if that will work first…and make sure patient uses the ENTIRE Course of care)
Bacterial Keratitis
- What is it?
- What will the patient have/feel?
- Often Associated with what?
- Main infecting organism in CL wearers that we’re wary of?
- Focal, White Opacity in the Corneal Stroma; May have OVERLYING ULCER
- Conj. Injection, FBS or Pain, Decrease VA, Photophobia, Discharge (Purulent or Mucopurulent)
- CL Wear
- Pseudomonas Aeruginosa.
* Also, Staph Aureus and Epidermidis and Pneumoniae. Strep Viridians, Etc.
Bacterial Keratitis Treatment
- What 2 Topical Drugs can be used?
- When should you use SYSTEMIC THERAPY?
a. Why are Fluoroquinolones useful?
b. Why do we use the newer agents? - What is the DOSAGE?
- Topical Fluoroquinolones and Topical Fortified Antibiotics
- When there is SCLERAL or INTRAOCULAR SPREAD of infection.
a. Because Most of the common infecting bacteria are GRAM NEGATIVE
b. it will DECREASE TREATMENT FAILURES due to resistance - 320-500 mg/kg po BID or QD, depending on the drug.
Preseptal Celulitis
- Pt may have a HISTORY of what 3 things?
- What are the 3 common Symptoms?
- May also have a MILD what?
- Pt will NOT HAVE what?
- Infecting Organism is usually what 3?
- Abrasion, Insect Bites, or Sinusitis
- Tenderness, Redness, Swelling of Eyelid and Periorbital Area
- a MILD Fever
- No Proptosis, Optic neuropathy, restriction of Eye movement, or pain w/Eye Movement
- Staph Aureus, Strep, Haemophilus, Influenzae
(Gram + and -)
Preseptal Cellulitis Treatment: Mild
- Augmentin
a. Children dosage?
b. Adults dosage? - What else can be given with similar dosing as Augmentin?
- Another drug?
- What drug can be given but is CI in children? (Dosage?)
- a. 20-40 mg/kg/day po in 3 divided doses
b. 400 mg po q8h for adults - Cefaclor, po
- Trimethoprim/Sulfamethoxazole (Bactrim), po
- Moxifloxacin (400 mg, po/iv qd)
Preseptal Cellulitis Treatment Moderate or Severe
- Who would be considered mod or severe?
- What should you do?
a. What should be given?
- CHILD LESS THAN 5 YEARS OLD, who appears TOXIC, or a PATIENT who DOES NOT improve on ORAL Antibiotics
- Admit to the hospital for IV Antibiotics.
a. Ampicillin/Sulbactam (Unasyn), Ceftriaxone, Moxifloxacin, Vancomycin
Traumatic Endophthalmitis
- May be due to what?
- Usual infecting organisms?
- Occult or Missed IOFB
2. Bacillus sp., Staph Epidermidis, Strep sp., other Negative Bacteria
Endophthalmitis Treatment
- Treat what if necessary?
- What Topical Antibiotics?
- What 3 Systemic Antibiotics and Dosages?
- Ruptured globe if necessary
- Fortified Tobramycin q1h, alternating w/Fortified Cefazolin or Vancomycin Every HALF HOUR
- a. Ciprofloxacin, 400 mg, iv, q12h
b. Moxifloxacin, 400 mg, po, qd
c. Cephazolin, 1g, iv, q48h
CAIs: Acetazolamide
- MOA?
- Ocular Use?
- Not generally used how to treat Glaucoma?
- Blocks Carbonic Anhydrase in CB, Decreases Aq. Humor Production
- Tx of ACUTE ANGLE CLOSURE
- ORALLY
CAIs: Acetazolamide: Adverse Effects
- What are they? (5)
- AVOID in Pt with what disease?
- a. Metabolic Acidosis (mild)
b. Potassium Depletion
c. Kidney Stone Formation
d. Drowsiness
e. Paresthesia - with Liver disease
CAIs: Acetazolamide: Major Interactions
- Can interact with what 5 drugs?
- Methenamine
- NSAIDs
- Pepto-Bismol
- Topiramate
- Salicylates
Acute Angle Closure
- Symptoms
a. What happens RAPIDLY?
b. What might they feel?
c. What will happen in SEVERE Cases? - Signs
a. Ciliary
b. AC
c. Pupil
d. Iris BVs?
e. IOP?
- a. Rapidly Progressive UNILATERAL Vision Loss
b. Periocular Pain and and Edema (may be mild)
c. Nausea and Vomiting in Severe cases - a. Ciliary Flush
b. Shallow AC w/Corneal Edema, Iridocorneal Contact, and/or Cells and Flare
c. Oval, Fixed Pupil
d. Dilated Iris BVs
e. SEVERELY ELEVATED IOP (50-100 mmHg)
Acute Angle Closure Treatment
- Option 1?
a. Do this provided there’s no what? - Option 2
a. Start with what?
b. Then do what?
c. If using DIAMOX SEQUELS for ORAL Dosing, give them what? - If there’s EMESIS, consider using ONLY what?
- 500 mg iv and 500 mg po
a. no emesis - a. 500 mg po
b. then 125-250 mg po/iv q4h
c. give 500 mg BID
3. only IV dosing