Pharmacological Management of Ocular Infection Flashcards

1
Q

What are the common antibacterials and types?

A
  • Aminoglycosides:
    o Gentamicin
    o Tobramycin
    o Neomycin
  • Cephalosporins, 2nd gen
    o Cefruroxime
  • Macrolides
    o Azithryomycin
  • Quinolones
    o Ciprofloxacin
    o Levofloxacin
    o Moxifloxacin
    o Ofloxacin
  • Other
    o Chloramphenicol
    o Fusidic acid
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2
Q

What are antimicrobial agents?

A
  • An agent, either natural or synthetic, that kills or inhibits growth of susceptible microorganisms – could be bacteria, viral or fungal
  • Antibiotic substance is produced by natural metabolic processes of some microorganisms that can inhibit or kill other microorganisms
    o Always derived from natural process
  • Antimicrobials may be further classified as antibacterial, antiviral or antiprotozoal, depending on type of organism against which they exert an effect
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3
Q

What are the main microorganisms associated with ocular infections?

A

Bacteria:
Staph aureus, streptococcus pneumoniae, neisseria gonorrhaea, pseudomonas aeruginosa*
Viruses:
Adenovirus, enterovirus, herpes simplex virus
Fungi:
Candida species
Protozoa:
Acanthamoeba species, naegleria species
* = particularly associated with CL use

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4
Q

What is bacteria?

A
  • Prokaryotic cells – does not have nucleus or membrane-bound organelles
  • Classification:
    o Many methodologies
    o Gram staining particularly important for classification of bacteria for purposes of using effective tx regimes
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5
Q

What is the action of antibactrial drugs?

A
  • Site of action of antibacterial agents is commonly:
    o The cell membrane (or more selectively the cell wall) - allows uptake of nutrients by passive diffusion – if disrupt function of cell wall then it cannot replicate
    o The ribosomes - the site of protein synthesis
    o DNA gyrase – replication of genetic material of bacterial cells  essential for bacterial replication – so if disrupt activities of DNA gyrase then that will hinder replication of bacterial cells
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6
Q

What is the mechanism, medicinal forms, indications and important points to note about aminoglycosides?

A
  • Mechanism
    o Interfere w/ ribosome function affecting protein synthesis
     By combining mRNA to produce an abnormal codon
    o Bacteriocidal – kills bacteria
    o Broad spectrum antibiotics, affecting protein synthesis taking place at ribosomes
     Mechanism is slightly different to chloramphenicol or fusidic acid. The aminoglycosides inhibit protein synthesis by disruption of the function of the 30S ribosomes causes a misreading of the peptidyl tRNA identities
  • This results in incorrect peptides & proteins being produced
     They have bacteriostatic effects as well as a slow bactericidal effect (esp. in gram negative bacteria) as it works on the bacterial cell membrane and may exert weak inhibitory effects on bacterial DNA replication
    o Generic is listed in BNF as non-proprietary
  • Medicinal Forms: available topical presentations
    o Gentamicin (0.3% Generic) (PoM)
    o (Tobramycin) – not currently available
    o Neomycin in combo w/ steroid product (PoM)
  • Indications:
    o Bacterial eye infections
  • TO NOTE:
    o Typically, not used as 1st line tx for bacterial conjunctivitis or bacterial keratitis as better for gram negative than gram positive bacteria
    o Gentamicin (and Tobramycin) used to treat P. Aeruginosa
     May be used in 2ndary care for pxs w/ CL associated keratitis
     Gentamicin 0.3% 3mg per 1ml 10ml
    o Neomycin – broader spectrum but not effective against P. Aeruginosa, currently only available in combination drops with dexamethasome and polymixicin B (Maxitrol)
    o Neomycin used in combo with steroids to treat post operative inflammation
     BUT becoming less commonly used for this purpose as now listed as “less suitable for prescribing” in BNF
    o Aminoglycosides can be toxic to OCULAR surface, typically response occurs after 1-2 weeks of use & is not serious typical undesirable effects as a result of ocular toxicity are punctate keratitis, injection of inferior cul de sac, and a weepy erythema with oedema of eyelid tissues
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7
Q

What are the cautions, interactions, contraindications, undesirable effects, info on pregnancy/breastfeeding for gentamicin (aminoglycoside)?

A

IP OPTOMS
* Cautions:
o Nephrotoxicity – kidneys
o Ototoxicity – damage to inner ear
 No evidence of above 2 when gentamicin used topically
o Neuromuscular blocking effects – can block neuromuscular transmission at the neuromuscular junction which can cause paralysis of effected the skeletal muscles – unlikely to happen in topical use
* Interactions:
o Concurrent use with other potentially nephrotoxic or ototoxic drugs should be avoided (unless considered essential)
 Potent diuretics such as ethacrynic acid & frusemide are believed to enhance any risk of ototoxicity whilst amphotericin B, cisplatin & cyclosporin & cephalosporins are potential enhancers of nephrotoxicity.
* Contraindications:
o In cases of known allergy to aminoglycosides
o Due to neuromuscular blocking effects contraindicated in myasthenia gravis & related conditions
* Undesirable effects:
o Local sensitivity; blurred vision, eye irritation, burning sensation, stinging sensation, itching
* Pregnancy & Breastfeeding:
o Usage in pregnancy should only be considered in life-threatening situations where expected benefits outweigh possible risks
o Amount of gentamicin ingested from milk is unlikely to result in significant blood levels in breast-fed infants – so is relatively safe to use gentamicin in mothers who are breast-feeding

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8
Q

Describe mechanism, medicinal forms, indications, cautions, interactions and pregnancy/breastfeeding info for cephalosporins?

A

None available topically but one available for use as intracameral injection
* Mechanism:
o Interferes with cell wall synthesis
o Bateriocidal
* Medicinal forms:
o Available for use as intracameral injection
o Cefuroxime (Aprokam intracameral injection) (PoM)
 Cefuroxime brand name APROKAM 1mg injected into the anterior vitreous at the end of cataract surgery
* Indications:
o Prophylaxis of endophthalmitis after cataract surgery
 Advocated for this purpose by the Scottish Medicines Consortium
* Cautions:
o Combined operations with cataract surgery – e.g. combined trabeculectomy with cataract surgery – use it with caution due to increased risks associated with that surgery
o Complicated cataract surgery – may wish not to use cefuroxime
o Reduced endothelial cell count
o Severe risk of infection
o Severe thyroid eye disease
* Interactions:
o More likely to cause nephrotoxicity if combined w/ other preparations such as aminoglycosides, methotrexate, acyclovir, ganciclovir, ketorolac
 More likely if these drugs are administered systemically
* Pregnancy & Breastfeeding:
o Safe to use in pregnancy, present in breastmilk in low concs (but still safe for use) – but unlikely for female who is of fertile age to be having cataract surgery

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9
Q

What is the mechanism, medicinal forms, indications, off label uses by opthalmology and resistance of macrolides?

A

IP OPTOMS
* Mechanism:
o Inhibits translocation during protein synthesis taking place at ribosomes
o Bacteriostatic effect by disrupting protein synthesis which involves binding to ribosomes – same site of action as chloramphenicol so if both agents are used simultaneously some competition at drug site may occur
o Reasonably broad spectrum
* Medicinal Forms:
o Available topic preparations
 Azithromycin (Azyter 1.5% SDU eye drops) (PoM) – 15mg per gram unit dose, bds for 3 days for both children & adults
 (Erythromycin) – only available in US
* Indications:
o Chlamydia trachomatis tx
 Macrolide antibiotic drugs block protein synthesis in bacteria, including Chlamydia (mechanism is slightly different from chloramphenicol, aminoglycosides, tetracyclines or fusidic acid) and they reduce the replication rate of bacteria.
o Bacterial conjunctivitis
o Also used off licensed in stubborn blepharitis
* Erythromycin most useful against gram +ve organisms & a few gram -ve organisms (such as N. Gonorrheae)
* Azithromycin commonly used for the treatment of blepharitis by ophthalmologists
o Use in blepharitis is off label
 Azyter has demonstrated notable additional anti-inflammatory activities when compared to standard eyelid care ie. Lid hygiene and hot compresses
 Some evidence that topical azithromycin gives a superior result to systemic azithromycin for blepharitis
* Other off label uses by ophthalmology:
o Topical erythromycin and systemic penicillin to treat neonatal N. Gonorrheae conjunctivitis
o Systemic erythromycin and topical azithromycin to treat neonatal chlamydial conjunctivitis
* Resistance to macrolides (not as much of a consideration when using topically, more so when systemically) is brought by modification of ribosomes & can occur when used widely as a prophylactic
o Has been shown to be case in group of children where erythromicin resistant staphylocci were found when these children had been administered erythromycin to prevent ophthalmia neonatorum
o That’s why it is never used prophylactically – only used in active infections

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10
Q

What are the cautions, interactions, contraindications, undesirable effects and info on pregnancy/breastfeeding for azithromycin (type of macrolide)?

A

IP OPTOMS
* Cautions:
o Pxs should be informed that tx should cease at end of 3 day course even if residual sxs remain
* Interactions:
o Many varied interactions – consult BNF – particularly problematic when prescribing systemic erythromycin
* Contraindications:
o Hypersensitivity to azithromycin, to any other macrolide (e.g. erythromycin) or to excipient Triglyceride – would not use Azyter if allergic to either of these
* Undesirable effects:
o Common:
 Eye discomfort
 Blurred vision
o Uncommon:
 Eye allergy
 Angioedema –area of swelling of lower layer of skin & tissue just under skin or mucous membranes.
* Swelling may occur in face, tongue, larynx, abdomen, or arms and legs. Often associated with hives, which are swelling within upper skin – can occur to periorbital skin when using topical agent
* Pregnancy & Breastfeeding:
o Listed as safe for use during pregnancy & breastfeeding
Need to discuss the frequency of undesirable effects with pxs when prescribing

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11
Q

Describe mechanism, medicinal forms, and indications of quinolones?

A

IP OPTOMS
* Extremely effective topical antibacterials
* Mechanism:
o Interferes with the production of DNA by inhibiting the enzyme (DNA gyrase) responsible for producing the coils of nucleic acid in the bacterial cells – inhibits protein metabolism
o Bacteriostatic
o Effective against gram +ve and gram -ve – broad spectrum
* Medicinal Forms:
o Available topical preparations
 Ciprofloxacin (Ciloxan 0.3% eyedrops) (PoM) – next cheapest drug in this class £4.70 per 5ml bottle
 Levofloxacin (Levofloxacin generic 5mg/ml eyedrops)(PoM) – there is a preservative free version of this available
 Moxifloxacin (Moxivig 0.5% eyedrops) (PoM)
 Ofloxacin (Exocin 0.3% eyedrops) (PoM) – v commonly used in practice – most cost-effective drug in this class £2.15 per 5ml bottle
* Indications:
o Ciprofloxacin indicated for superficial bacterial eye infections, severe superficial eye infections, and corneal ulcers
o The other drugs in this class are indicated for eye infections

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12
Q

What are the cautions, interactions, contraindications, undesirable effects, info on pregnancy/breastfeeding for ofloxacin (type of quinolone)?

A

IP OPTOMS
* Cautions:
o Safety & effectiveness in infants below age of 1 year have not been established – so should be used with EXTREME caution in this age group
o Caution should be taken in patients w/ known risk factors for prolongation of 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 (systemic), antipsychotics)
 Cardiac disease (e.g. heart failure, myocardial infarction, bradycardia)
 Elderly patients & women may be more sensitive to QTc-prolonging medications. Therefore, caution should be taken when using fluoroquinolones, including EXOCIN® (topical quinolone), in these populations
 Use with caution in pxs with uncorrected electrolyte imbalance (e.g. hypokalaemia, hypomagnesaemia)
 The above 4 points apply more to systemic application rather than topical application (except point 3)
* Interactions:
o As per above
* Contraindications:
o In those with known allergy to drug or excipients in formulation
* Undesirable effects:
o Eye irritation & ocular discomfort
o Ventricular arrhythmia – reported predominantly in pxs w/ risk factors for QT prolongation
* Pregnancy & Breastfeeding:
o Not suitable for use during pregnancy & breastfeeding
Use in pregnancy: There have been no adequate & well-controlled studies performed in pregnant women. Since systemic quinolones have been shown to cause arthropathy in immature animals, it is recommended that EXOCIN® not be used in pregnant women.
Use during lactation: Because ofloxacin and other quinolones taken systemically are excreted in breast milk, and there is potential for harm to nursing infants, a decision should be made whether to temporarily discontinue nursing or not to administer the drug, taking into account the importance of the drug to the mother

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13
Q

What is the mechanism, medicinal forms, indications, dose, cautions, interactions, contraindications, undesirable effect and pregnancy/breastfeeding info for chloramphenicol?

A

Exempted PoM
* Mechanism:
o Inhibition of protein synthesis by interaction with bacterial ribosomes
 Protein synthesis requires amino acids to be brought to ribosome sites, arranged in correct sequence & linked to the one next to it
 Chloramphenicol blocks this linking of the amino acids resulting in a reduction and eventual halt in the overall rate of cell division.
 However, resistance to chloramphenicol can occur as a result of alterations (mutations) in the ribosome binding sites
* Little evidence of this resistance occurring in topical chloramphenicol
o Bacteriostatic
* Medicinal Forms:
o Available topical preparations
 Chloramphenicol generic 0.5% eyedrops (5ml bottle and SDUs) (PoM)
 Chloramphenicol generic 1% eye ointment (PoM)
* Both available as exempted PoMs for optoms
* Indications:
o Superficial eye infections – when used as PoM
o When used as P med – only indicated for bacterial conjunctivitis
* Dose:
o 0.5% eyedrops: apply one drop into the infected eye every 2 hrs 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 within this time).
o 1% eye ointment: put a small amount into affected eye 4 times a day for 2 days, and then twice a day for 5 days.
* Cautions:
o Risk of aplastic anaemia after topical chloramphenicol use is less than 1 per million tx courses
* Interactions:
o Safety for use during pregnancy & breastfeeding has not been established
o Avoid in pxs taking drugs liable to depress bone marrow function
* Contraindications:
o Hypersensitivity to drug or any of excipients
o Immune system deficits: Hypersensitivity reactions including angioedema, anaphylaxis, urticaria, fever, vesicular and maculopapular dermatitis
o Blood & Lymphatic system disorders: Bone marrow depression and rarely aplastic anaemia has been reported following topical use of chloramphenicol. Whilst the hazard is a rare one, it should be borne in mind when assessing the benefits expected from the use of this compound
 Above 2 points are only theoretical risks when applying chloramphenicol topically
o Known personal or FH of blood dyscarsias, including aplastic anaemia
* Undesirable effect:
o Transient irritation, burning, stinging, itching & dermatitis on skin around eye
* Pregnancy & Breastfeeding:
o Not recommended in either

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14
Q

What is other info to know about chloramphenicol?

A
  • Potent broad spectrum (effective against both gram positive and negative)
  • Ineffective against pseudomonas aeruginosa (gram -ve bacteria) – so if px CL wearer and has eye infection, chloramphenicol SHOULD NOT BE USED AS 1ST LINE AGENT
  • Widely used due to:
    o Broad spectrum
    o Good corneal penetration
    o Little cross resistance – when used topically
  • PoM: 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
  • 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 +
    o Chloramphenicol has a dual classification. When classified a POM it can be used from 1 month. When as a P medicine for 2 years and over
  • 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
  • P med: 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
  • For details of the latest drug preparations see the BNF, however this may not list all P meds
    More and more toddlers coming to optoms with bacterial conjunctivitis – knowing your rights & knowing way you can use the legislation means can treat 6mth old baby if feel within your competence & so long as used via a signed order.
    If supplying directly to px (without signed order) – can only use it in bacterial conjunctivitis (cannot use it for e.g. hordeolum) & can only use it in children >2yrs.
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15
Q

What is the mechanism, medicinal forms, indications, dose, caution, interactions, contraindications, undesirable effects and info on pregnancy/breastfeeding for fusidic acid?

A
  • Mechanism:
    o Inhibition of protein synthesis taking place at ribosomes by inhibiting DNA translocation but does not bind to ribosomes
    o Chemically related to the cephalosporin antibiotics, but is a protein synthesis inhibitor
    o Mechanism of action of fusidic acid is similar to that of chloramphenicol, tetracyclines and te macrolides
    o Fusidic acid is a translocase inhibitor, indirectly interfering with translocase enzyme (by binding to a protein associated with the enzyme). If the translocase is blocked, the incoming peptidyl tRNA molecules cannot bind and protein synthesis is stopped
    o Bacteriostatic – when used in clinically recommended doses
     But at high doses can exert a slow bactericidal effect
  • Medicinal Forms:
    o Available topical preparations
     Fusidic acid 1% viscous eye drops – exempted PoM
  • Indications:
    o Staphylococcal eye infections – particularly good for gram +ve bacteria
  • Dose:
    o Apply twice daily, tx should be continued for at least 48hrs after the eye returns to normal
  • Cautions:
    o Not to be worn w/ CLs – microcrystalline fusidic acid may cause scratches in the contact lens or cornea. Contact lenses are kept out until all symptoms of the infection have gone.
    o Contains BAK which can cause eye irritation & CL discolouration
  • Interactions:
    o Systemic interactions are unlikely since systemic exposure after application of Fusidic acid eye drops is negligible
  • Contraindications:
    o Hypersensitivity to drug or any excipients – including BAK
  • Undesirable Effects:
    o Common: blurred vision (thick preparation), burning, redness & stinging on application
    o Uncommon: hypersensitivity, eyelid oedema, lacrimation, skin rash, angioedema
  • Pregnancy & Breastfeeding:
    o Can be used during pregnancy & breastfeeding
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16
Q

What is other important info on fusidic acid?

A
  • Potent narrow spectrum antibiotic, effective against gram +ve bacteria, in particular staphylococcus aeureus
  • Tx of marginal keratitis, blepharitis, bacterial conjunctivitis when gram +ve bacteria are thought to be causative organism
  • V 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
    o Now only used in cases of absolute need
  • Can be used on children of any age – so occasionally still is a precedent to use it
  • Fusidic acid should not be used with quinolones, with which they are antagonistic
17
Q

What is the mechanism, medicinal forms and indications for toptical antiprotazoal/antibacterial?

A

IP/Entry Level - available as P Med
* Mechanism:
o Aromatic diamidine disinfectant w/ antibacterial, antiprotozoal & antifungal actions
* Medicinal Forms:
o 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)
* Indications:
o It may be used topically for the treatment of minor eye infections such as conjunctivitis and blepharitis
o Used by medics primarily for antiprotozoal and antifungal properties

18
Q

Describe propramidine isetionate and its cautions, interactions, contraindications, undesirable effects and info on pregnancy/breastfeeding?

A

Available as P Med - antiprotozoal/antibacterial
* Propamidine isetionate is active against Gram +ve non-spore forming organisms, but less active against Gram -ve bacteria & 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 – e.g. if someone has conjunctivitis with a lot of purulent discharge if it is a gram +ve organism
* Cautions:
o If no significant improvement after 2 days discontinue and consult a physician
o Unsuitable for use with contact lenses – due to preservatives in the preparation
o If vision is disturbed or becomes worse during the treatment regime discontinue and consult a physician – with some urgency
* Interactions:
o None known
* Contraindications:
o Hypersensitivity to the drug or any excipients e.g. the preservative
* Undesirable Effects:
o Eye discomfort, blurred vision, few systemic effects
* Pregnancy and Breastfeeding:
o Not suitable during pregnancy or breastfeeding

19
Q

Describe viruses?

A
  • Simple noncellular structures – lack several characteristics of living things, except ability to replicate which they can accomplish when they are contained within prokaryotic or eukaryotic cells
  • Contain nucleic acid (in form of single or double-stranded RNA or DNA – not both) and a capsid (protein coat) – these two together are known as nucleocapsid
  • Sometimes an envelope (an additional glycoprotein coat around the capsid) and a tail
    o Viruses without envelope  naked viruses
  • Capsids are formed from identical protein subunits, called capsomeres, which assemble into repeating, three-dimensional, symmetrical structures of which there are two major classes:
    o Helical: the protein subunits and the nucleic acid are arranged in a helix;
    o Icosahedral: the protein subunits assemble into a 20-sided symmetric shell that covers the nucleic acid-containing core
  • Are considered neither prokaryotes nor eukaryotes as they lack several characteristics of living things, except ability to replicate (which they accomplish only in living cells)
  • Pathogenesis of viral infection consists of several different steps
    o Initially virus must enter a host. Entrance may be accomplished through one of the body surfaces, for example skin, respiratory system, gastrointestinal system, urogenital system or conjunctiva of eye.
    o Some viruses enter host by way of needle injuries, blood transfusions and organ transplants, or by means of insect vectors which transmit the virus from one host to another
20
Q

What is the action of antiviral drugs?

A
  • Topical antiviral drugs are active against herpes simplex & herpes zoster
  • 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 epithelial cells) are active against the virus
    o The drugs themselves are largely ineffective against the virus, but will be biotransformed inside virus-infected corneal epithelial or conjunctival epithelial cells into the active form of the drug
  • The active drug blocks DNA transcription leading to DNA that is fragmented and no longer functional as a template for subsequent mRNA & later protein synthesis
    o As a result, the herpes virus fails to replicate
  • These drugs can be toxic to corneal epithelial cells, so needs to be used cautiously
21
Q

Describe the mechanism, medicinal forms and indications of topical antiviral?

A

IP OPTOMS
* Mechanism:
o Block actions of viral DNA/RNA polymerase enzymes
* Medicinal Forms:
o Available topical preparations
 Aciclovir 3% ophthalmic ointment (Zoviraz) (PoM) – stopped being produced
 Ganciclovir 0.15% eye ointment (Virgan) (PoM) – only one available
* Indications:
o Herpes simplex keratitis – other viral infections are not susceptible to ganciclovir – ganciclovir not effective against adenovirus or enterovirus

22
Q

Describe ganciclovir and cautions, interactions, contraindications, undesirable effects and info on pregnancy/breastfeeding?

A

Ganciclovir (type of topical antiviral): IP OPTOMS ONLY - PoM
* Available on PGD’s in some local shared care schemes in Scotland
* Can be used by IP optom (& optoms 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 (efficacy not been established in children so not recommended under age 18)
* Not effective against other viral organisms which can cause conjunctivitis e.g.not effective against adenovirus
* College Guidance on Tx of HSK:
o When infection is stromal, atypical or diagnosis is in doubt, or px is a CL wearer – then that px is more appropriately managed within ophthalmology
* Cautions:
o Stinging on instillation
o Avoid wearing CLs during treatment regime
o Avoid if known hypersensitivity to acyclovir or valaciclovir (antiviral tx used more systemically)
o Topical antivirals can be toxic to corneal epithelial cells therefore should be used with caution
* Interactions:
o The concomitant administration of Chloramphenicol with other drugs liable to depress bone marrow function should be avoided
* Contraindications:
o Hypersensitivity to the active drug or to any of the excipients – including BAK
o Myelosuprresssion during previous exposure to chloramphenicol
 If someone had aplastic anaemia after using chloramphenicol
o Known personal or family history of blood dyscrasias including aplastic anaemia
* Undesirable Effects:
o Very common SPK (however, this did not necessitate an early termination of treatment and healed without sequaele).
o Common – transient stinging on instillation, conjunctivitis
o Rare – Blepharitis
o Very rare – Immediate hypersensitivity reactions including angioedema and urticaria.
* Pregnancy and Breastfeeding:
o Manufacturer advises avoid unless no suitable alternative – limited information available
o Ganciclovir may be used in pregnancy when benefits outweigh risks
o Safe for use during breastfeeding