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Zirgan Side Effects

Generic Name: ganciclovir ophthalmic

Note: This page contains side effects data for the generic drug ganciclovir ophthalmic. It is possible that some of the dosage forms included below may not apply to the brand name Zirgan.

For the Consumer

Applies to ganciclovir ophthalmic: intraocular implant

Other dosage forms:

As well as its needed effects, ganciclovir ophthalmic (the active ingredient contained in Zirgan) may cause unwanted side effects that require medical attention.

Also, ganciclovir has been found to cause cancerous tumors in animals. Discuss these possible effects with your doctor.

If any of the following side effects occur while taking ganciclovir ophthalmic, check with your doctor or nurse as soon as possible:

More common—Usually occur within the first 2 months after the surgery
  • Decrease in vision (severe)
  • seeing flashes or sparks of light
  • seeing floating spots before the eyes, or a veil or curtain appearing across part of vision
Less common—Usually occur within the first 2 months after the surgery
  • Blurred vision or other change in vision
  • decreased vision or other change in vision
  • eye pain or tearing
  • red or bloodshot eye
  • sensitivity of eye to light
Rare—Usually occur within the first 2 months after the surgery
  • Eye irritation
  • swelling of the membrane covering the white part of the eye

Some ganciclovir ophthalmic side effects may not need any medical attention. As your body gets used to the medicine these side effects may disappear. Your health care professional may be able to help you prevent or reduce these side effects, but do check with them if any of the following side effects continue, or if you are concerned about them:

More common
  • Decrease in vision lasting approximately 2 to 4 weeks

For Healthcare Professionals

Applies to ganciclovir ophthalmic: intraocular implant, ophthalmic gel


Ocular side effects that occur with ganciclovir ophthalmic (the active ingredient contained in Zirgan) implant are generally confined to the implanted eye. Some of these events (e.g. retinal detachment) will also occur with the natural progression of CMV retinitis and may not necessarily be direct complications of the surgical procedure. However, it is possible that the implant may precipitate some of these conditions.

The most common side effect is a decrease in visual acuity, which occurs in nearly all patients immediately following the implant procedure and lasts 2 to 4 weeks in most cases. In 10% to 20% of the patients, visual acuity loss of 3 lines or more may occur during the first two months postoperatively, as well as vitreous hemorrhage and retinal detachment. Additionally, cataract formation or lens opacities, macular abnormalities, increases in intraocular pressure, optic disc and nerve changes, hyphemas, and uveitis may occur in up to 5% of patients.

Observed in less than 1% of patients are retinopathy, synechia, suprachoroidal hemorrhage, cotton wool spots, keratopathy, astigmatism, endophthalmitis, microangiopathy, sclerosis, choroiditis, chemosis, phthisis bulbi, angle closure traction, hypotony, retinal tear, corneal dellen, choroidal folds, and gliosis. Permanent loss of vision due to endophthalmitis has been reported.

Intravitreous injections of ganciclovir have resulted in scleral induration, corneal ulceration, chemical irritation, cataract formation, transient elevations in intraocular pressure, optic disc and nerve atrophy, vitreous haze, iritis, vitreous and conjunctival hemorrhage, retinal detachment, and infectious endophthalmitis. One case of retinal toxicity and necrosis resulting in visual loss was reported in a patient inadvertently given 40 mg of ganciclovir.

Side effects of ganciclovir ophthalmic gel have included blurred vision (60%), eye irritation (20%), punctate keratitis (5%), and conjunctival hyperemia (5%).[Ref]


Complications related to the removal of ganciclovir implants have been reported. Rare cases of medical pellet separation from its tab have been reported.[Ref]


1. Saran BR, Maguire AM "Retinal toxicity of high dose intravitreal ganciclovir." Retina 14 (1994): 248-52

2. Martin DF, Parks DJ, Mellow SD, Ferris FL, Walton RC, Remaley NA, Chew EY, Ashton P, Davis MD, Nussenblatt RB "Treatment of cytomegalovirus retinitis with an intraocular sustained- release ganciclovir implant. A randomized controlled clinical trial." Arch Ophthalmol 112 (1994): 1531-9

3. "Product Information. Vitrasert (ganciclovir ophthalmic)." Chiron Therapeutics, Emeryville, CA.

4. Melchior WR, Bindlish V, Rybak MJ "Intravitreal ganciclovir for cytomegalovirus retinitis in AIDS patients." Ann Pharmacother 26 (1992): 36-7

5. Collazos J, Diaz F, Mayo J, Martinez E, Fernandez A "Endophthalmitis as a complication of intravitreal treatment for cytomegalovirus retinitis." AIDS 9 (1995): 980-1

6. Cochereau-Massin I, Lehoang P, Lautier-Frau M, Zazoun L, Marcel P, Robinet M, Matheron S, Katlama C, Gharakhanian S, Rozenbaum W, et al "Efficacy and tolerance of intravitreal ganciclovir in cytomegalovirus retinitis in acquired immune deficiency syndrome." Ophthalmology 98 (1991): 1348-53;disc. 1353-5

7. Cantrill HL, Henry K, Melroe NH, Knobloch WH, Ramsay RC, Balfour HH Jr "Treatment of cytomegalovirus retinitis with intravitreal ganciclovir. Long-term results." Ophthalmology 96 (1989): 367-74

8. Engstrom RE, Holland GN "Local therapy for cytomegalovirus retinopathy." Am J Ophthalmol 120 (1995): 376-85

9. Sanborn GE, Anand R, Torti RE, Nightingale SD, Cal SX, Yates B, Ashton P, Smith T "Sustained-release ganciclovir therapy for treatment of cytomegalovirus retinitis. Use of an intravitreal device." Arch Ophthalmol 110 (1992): 188-95

10. Anand R, Nightingale SD, Fish RH, Smith TJ, Ashton P "Control of cytomegalovirus retinitis using sustained release of intraocular ganciclovir." Arch Ophthalmol 111 (1993): 223-7

11. Boyer DS, Posalski J "Potential complication associated with removal of ganciclovir implants." Am J Ophthalmol 127 (1999): 349-50

It is possible that some side effects of Zirgan may not have been reported. These can be reported to the FDA here. Always consult a healthcare professional for medical advice.

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