anti viral drugs in ophthalmology

Dr. Ankit M. PunjabiDOMS (Final Year), Dept of Ophthalmology,

KIMS Hospital, BangaloreKarnataka, INDIA

Email: drankitalways@gmail.com

1. Smallest living unit2. Nutrition from host3. Difficult to Rx4. Difficult to diagnose

DNA Viruses1. Herpes group HSV & HZV CMV2. Adeno viruses3. Variola & Vaccinia4. Molluscum contagiosum5. HPV

RNA Viruses1. Picorna viruses2. Measles3. Mumps4. Rubella

1. Adsorption2. Entry3. Uncoating4. Transcription5. Virus component synthesis

Ist Generation drugs

1. Idoxuridine2. Vidarabine3. Trifluorothymidine4. Cytarabine

2nd Generation Drugs1. Acyclovir2. Bromo vinyl deoxyuridine3. Interferons4. Famiclovir5. Vabaciclovir6. Foscarnet7. Ganciclovir

8. Zidovudine9. Sorvudine

Thymidine analogue Activated by cellular & viral kinase Incorporation into viral genome Faulty virus synthesis

TOXICITY1. SPK2. Indolent ulceration3. Delayed epithelial healing4. Stromal opacification5. Chemosis6. Hyperaemia7. Follicles

8. Eyelid edema9. Meibomian gland plugging10. Punctal occlusion

DOSE 0.1% e/d and 0.5% e/o

1. Idurin 0.1%2. Ridinox 0.1%3. Toxil 0.1%

Acute and Recurrent Herpetic keratoconjuctivitis

KeratitisPurine nucleoside analoguePhosphorylation by host kinases

Chain terminator for new viral DNA

Doesnot require viral thymidine kinase

Not effective against RNA viruses

Side effects1. Irritation2. SPK3. Pain 4. Photophobia5. Punctal occlusion6. Secondary glaucoma7. Corneal vascularisation

Fluorinated pyrimidine Thymidine analogue Phosphorylated to active form More conc. In infected cells Drug of choice for HSV Keratitis Water and lipid soluble Drug of choice for HSV

Side Effects1. Burning & Stingy sensation2. Hyperaemia3. Keratitis sicca4. Delayed wound healing5. Raised IOP

DOSE

1% Solution 6 – 9 times till epithelium heals then, 1 drop 4 times/day for week

Acyclic nucleoside analogue of Guanosine Selective for herpes infected cells Thymidine kinase & DNA polymerase Chain termination Oral, Topical, Intravenous administration

DOSE1. Topical – 3% Ointment2. Systemic – 1g/ 24 hr for 10 days 200mg, 400mg, 800mg Tablets3. Intravenous 5 mg/ kg 8 hrly for 5 – 10 days

INDICATIONS1. Primary HSV2. Infectious epithelial keratitis3. HSV iritis & blepharitis4. Risk of recurrence of infectious ds.5. Post PK for HSV6. ARN7. Immunosuppressed patients

SIDE EFFECTS1. SPK2. Burning sensation3. GIT disturbances, nausea, diziness4. Renal dysfunction5. Iv rashes, fall in BP

1. Acivir2. Cyclovir3. Ocuvir4. Syslovir5. Virucid6. Zovirax ophthalmic oint.

Guanine analogue Structurally related to acyclovir CMV retinitis

INDICATIONS1. CMV Retinitis2. Prevention in immunosuppresed patients

C/I Hyperesensitivity to acyclovir or

ganciclovir

DOSE1. CMV retinitis Induction regime 5mg/kg every 12 hrs for 14-21 days Maintenance regime 5 mg/kg/hr once daily/ week or 6 mg/kg once daily 5 days /week

Oral, for maintenance only 1000 mg 3 times daily or 500 mg 6 times daily every 3 hrs.

Prevention 5 mg/Kg every 12 hrs for 7 –14 days Then, 5 mg/kg once daily / week or 6 mg/Kg once daily 5 days / week

Ganciclovir intravitreal implant1. Rx of CMV retinitis2. 4.5 mg of drug3. Released over 6 – 8 months4. Stored at 15 – 30 * C

1. Glycoproteins2. Host cell in response to viral infection3. Broad antiviral, Immunomodulator & Anti-proliferative4. Three types

INDICATIONS1. Herpes Zoster2. AIDS related Kaposi’s sarcoma

DOSE 30 – 400 million/ml once or twice a day for

2 weeks

Adverse effects1. Fever, chills, Myalgia2. Bonemarrow depression3. Neurotoxicity4. Hypersenstivity

Tri-sodium salt of phosphoformic acid Inhibits viral DNA replication Acyclovir and Ganciclovir resistant Renal excretion

DOSE

60 mg/Kg every 8 hrs for 2 –3 weeks Maintenance 90 – 120 Mg/Kg over 2 hrs once daily

1. Bromovinyl deoxyuridine2. HPMPC