Week 7 - Pharmalogical managment of ocular infections Flashcards

Question

Quinolones: medical forms

Answer 1

**Medicinal Forms** Available topical preparations • Ciprofloxacin (Ciloxan 0.3% eyedrops) (PoM) • Levofloxacin (Levofloxacin generic 5mg/ml eyedrops) (PoM) • Moxifloxacin (Moxivig 0.5% eyedrops) (PoM) • Ofloxacin (Exocin 0.3% eyedrops) (PoM)

Answer 2

Cautions • Safety and effectiveness in infants below the age of one year have not been established. •Caution should be taken in patients with known risk factors for prolongation of the QT interval such as, for example: - concomitant use of drugs that are known to prolong the QT interval (e.g. Class IA and III anti-arrhythmics, tricyclic antidepressants, macrolides, antipsychotics) - cardiac disease (e.g. heart failure, myocardial infarction, bradycardia) - elderly patients and women may be more sensitive to QTc-prolonging medications. Therefore, caution should be taken when using fluoroquinolones, including EXOCIN®, in these populations. **Interactions** - as per above **IP OPTOMETRISTS**

Answer 3

**Contraindications** • Contraindicated in those with a known allergy to the drug or the excipients in the formulation **Undesirable Effects** • Eye irritation and ocular discomfort •Ventricular arrhythmia(reported predominantly in patients with risk factors for QT prolongation) **Pregnancy and Breastfeeding** • Not suitable for use during pregnancy or breastfeeding **IP OPTOMETRIST ONLY**

Answer 4

**Mechanism** • Inhibition of protein synthesis by interaction with bacterial ribosomes • Bacteriostatic **Medicinal Forms** Available topical preparations • Chloramphenicol generic 0.5% eyedrops (5ml bottle and SDUs) (PoM) • Chloramphenicol generic 1% eye ointment (PoM) **Indications** •Superficial eye infections **ENTRY LEVEL OPTOMETRISTS**

Answer 5

• **0.5% eyedrops;** one drop into the infected eye every two hours for 48 hours. After this period, treatment should be every four hours during waking hours. Eye drops may be supplemented by ointment at night. The course of treatment should last five days (even if symptoms improve). • **1% eye ointment:** put a small amount into the affected eye four times a day for two days, and then twice a day for five days.

Answer 6

• Potent broad spectrum (effective against both gram positive and negative) • Ineffective against pseudomonas aeruginosa • Widely used due to: - Broad spectrum - Good corneal penetration - Little cross resistance • Used in management of bacterial conjunctivitis, hordeolum, staphylococcal and seborrheic blepharitis, nasolacrimal duct obstruction where there is evidence of infection, dacryocystitis, marginal keratitis. • Cost-effective treatment

Answer 7

• Can be used age 2 years + when supplied directly by an entry level optometrist, can write a written order as an exempted POM for patients from age 1 month + • Important to note that chloramphenicol is available as various branded eye drops and eye ointments, which are P meds, e.g. Optrex infected eyes, eye drops 0.5% chloramphenicol • These preparations are only suitable for treatment of acute bacterial conjunctivitis, and can only be used in patients over age 2 and can only be used for a maximum of 5 days

Answer 8

**Cautions** • Risk of aplastic anemia after topical chloramphenicol use is less than one per million treatment courses **Interactions** • Safety for use during pregnancy and breastfeeding has not been established • Avoid in patients taking drugs liable to depress bone marrow function

Answer 9

**Contraindications** • Hypersensitivity to the drug or any of the excipients • Known personal or FH of blood dyscrasias, including aplastic anaemia **Undesirable Effects** Transient irritation, burning, stinging, itching and dermatitis **Pregnancy and Breastfeeding** Not recommended during pregnancy or breastfeeding

Answer 10

**Mechanism** • Inhibition of protein synthesis by inhibiting DNA translocation •Bacteriostatic **Medicinal Forms** Available topical preparations • Fusidic Acid 1% viscous eye drops(exempted PoM) **Indications** • Staphylococcal eye infections **Dose** Apply twice daily, Treatment should be continued for at least 48 hours after the eye returns to normal. **ENTRY LEVEL OPTOMETRIST**

Answer 11

• Potent narrow spectrum antibiotic, effective against gram positive bacteria, in particular staphylococcus aureus • Treatment of marginal keratitis, blepharitis, conjunctivitis • Very expensive currently, since Fusithalmic viscous eye drops are no longer available only product available is fusidic acid cost **£29.06** per 5g tube • As a result has been removed from many local formularies • Can be used on children of any age **ENTRY LEVEL OPTOMETRIST**

Answer 12

**Cautions** •Not to be worn with contact lenses • Contains BAK which can cause eye irritation and contact lens discolouration **Interactions** • Systemic interactions are unlikely since systemic exposure after application of Fusidic acid eye drops is negligible **ENTRY LEVEL OPTOMETRIST**

Answer 13

**Contraindications** • Hypersensitivity to the drug or any excipients **Undesirable Effects** •Common blurred vision, burning, redness and stinging on application • Uncommon hypersensitivity, eyelid oedema, lacrimation, skin rash, angiodema **Pregnancy and Breastfeeding** • Can be used during pregnancy and breastfeeding

Answer 14

**Mechanism** • Aromatic diamidine disinfectant with antibacterial, antiprotozoal and antifungal actions **Indications** • It may be used topically for the treatment of minor eye infections such as conjunctivitis and blepharitis. **ENTRY LEVEL OPTOMETRIST**

Answer 15

**Medicinal Forms** Available topical preparations • Propamidine isethionate 0.1% eye drops (Brolene eye drops) (P) •Dibrompropamidine 0.15% eye ointment (GoldenEye ointment)(P) •Propramidine isethionate 0.1% eye drops (GoldenEye drops) (P) **ENTRY LEVEL OPTOMETRIST**

Answer 16

• Propamidine isetionate is active against Gram-positive non-spore forming organisms, but less active against Gram-negative bacteria and spore forming organisms. It also has antifungal properties. • It may be used off license in the treatment of acanthamoeba keratitis by specialists only • Works well even in the presence of copious purulent discharge

Answer 17

**Cautions** • If no significant improvement after 2 days discontinue and consult a physician • Unsuitable for use with contact lenses • If vision is disturbed or becomes worse during the treatment regime discontinue and consult a physician **Interactions** None known

Answer 18

**Contraindications** - Hypersensitivity to the drug or any excipients **Undesirable Effects** - Eye discomfort, blurred vision **Pregnancy and Breastfeeding** - Not suitable during pregnancy or breastfeeding

Answer 19

• Simple noncellular structures • Contain nucleic acid and a capsid(protein coat) • Sometimes an envelope (an additional glycoprotein coat around the capsid) and a tail

Answer 20

• Topical antiviral drugs are active against herpes simplex • Block the ability of the virus to replicate DNA • Topical antivirals (acyclovir and ganciclovir are prodrugs i.e. once biotransformed inside virus infected corneal and conjunctival cells are active against the virus • The active drug blocks DNA transcription leading toDNA that is fragmented and no longer functional, as a result herpes simplex fails to replicate

Answer 21

** Mechanism** Block the actions of viral DNA/RNA polymerase enzymes **Medicinal Forms** Available topical preparations •Aciclovir 3% ophthalmic ointment (Zoviraz) (PoM) •Gancilovir 0.15% eye ointment (Virgan) (PoM) **Indications** Herpes simplex keratitis **IP OPTOMETRISTS ONLY**

Answer 22

• Available on PGD's in some local shared care schemes in Scotland • Can be used by IP optometrists ( and optometrists using PGD's) to treat uncomplicated superficial acute or recurrent herpes simplex keratitis • Aciclovir may be used in children but use of ganciclovir in children is not recommended ( not recommended under age 18) • Not effective against other viral organisms which can cause conjunctivitis e. adenovirus

Answer 23

**Cautions** • Stinging on instillation • Avoid wearing contact lenses during treatment regime • Avoid if known hypersensitivity to acyclovir or valaciclovir **Interactions** • The concomitant administration of Chloramphenicol with other drugs liable to depress bone marrow function should be avoided **Contraindications** • Hypersensitivity to the active drug or to any of the excipients • Myelosuprresssion during previous exposure to chloramphenicol. • Known personal or family history of blood dyscrasias including aplastic anaemia

Answer 24

**Undesirable Effects** • Very common SP (however, this did not necessitate an early termination of treatment and healed without sequaele). • Common - transient stinging on instillation, conjunctivitis • Rare - Blepharitis • Very rare - Immediate hypersensitivity reactions including angioedema and urticaria. **Pregnancy and Breastfeeding** • Manufacturer advises avoid unless no suitable alternative - limited information available