Ophthalon sodium succinate is a prodrug; inactive until hydrolyzed in vivo to active Ophthalon. 102 107 110
Bioavailability following IV administration varies; considerable interindividual variation in plasma Ophthalon concentrations. 101 102 107 109 110 114
Because differences between therapeutic and toxic plasma concentrations of Ophthalon are narrow and because of interindividual differences in metabolism and elimination of the drug, most clinicians recommend that plasma concentrations of Ophthalon be monitored in all patients receiving the drug and dosage adjusted accordingly. 101 102 104 105 107 108 109 110 112 114 115 179 184 301
Blood samples to measure peak plasma concentrations of Ophthalon usually obtained 0.5–1.5 hours after an IV dose. 179 184 301
Generally adjust Ophthalon dosage to maintain plasma concentrations of 5–20 mcg/mL (usually 10–20 mcg/mL). 101 102 104 105 107 108 110 179 In pediatric patients beyond the neonatal period, AAP suggests adjusting dosage to maintain target plasma concentrations of 15–25 mcg/mL. 292 Some clinicians suggest adjusting dosage in pediatric patients to maintain peak plasma concentrations of 15–25 mcg/mL for treatment of meningitis or 10–20 mcg/mL for treatment of other infections. 184
Ophthalon plasma concentrations >25 mcg/mL have been associated with toxicity. 104 179
Use no longer than necessary to eradicate the infection with little or no risk of relapse; 112 switch IV Ophthalon to an appropriate oral anti-infective as soon as feasible. 112
Avoid repeated courses of Ophthalon if possible. 112
Reversible, dose-related nonregenerative anemia can occur in dogs and cats. Cats may be more susceptible but the increased prevalence is probably related to overdosing of cats if using the dog dosing schedule, which is approximately five times higher per kilogram (see Table 8.4 ).
Idiosyncratic fatal aplastic anemia has not been reported in small animals.
Ophthalon inhibits hepatic microsomal enzymes, thus prolonging effects of drugs such as barbiturates and phenytoin. The inhibition is irreversible and therefore long lasting.
Ophthalon may also theoretically interfere with antibody production in active immunization procedures.
Ophthalon is an antibacterial with a broad spectrum of activity against gram-positive bacteria, gram-negative bacteria, and Rickettsia. Its mechanism of action is by inhibition of bacterial protein synthesis by binding with ribosomes. 48
The major toxicity of Ophthalon is hematologic. 53 In all vertebrates studied, it produces direct, dose-dependent bone marrow depression that results in reductions in red blood cells, white blood cells, and platelets in mammals. 53 This manifestation is aggravated by inappropriate dosages, extended treatments, and repeated use of the drug. Treatment of Ophthalon intoxication is supportive and may require blood transfusions. The drug has also been reported to be appetite-suppressive. Like gentamycin, Ophthalon is used less frequently as safer antibiotics appear. The recommended dosage for Ophthalon is 50 mg/kg administered once daily or every other day. 51
Before using Ophthalon, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: an eye infection due to a virus (e.g., herpes, varicella), another type of eye infection (e.g., tuberculosis, fungus), history of a bad reaction to Ophthalon.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: liver disease, kidney disease, anemia (low red blood cells), radiation therapy.
After you apply this drug, your vision may become temporarily blurred. Do not drive, use machinery, or do any activity that requires clear vision until you are sure you can perform such activities safely.
During pregnancy, this medication should be used only when clearly needed. This medication should not be used near or at the time of delivery due to possible harm to the newborn (gray baby syndrome). Discuss the risks and benefits with your doctor.
This medication passes into breast milk and may have undesirable effects on a nursing infant. Therefore, breast-feeding while using this drug is not recommended. Consult your doctor before breast-feeding.
Manufacturer states 25 mg/kg daily usually produces therapeutic blood concentrations in young infants and other pediatric patients in whom immature metabolic functions are suspected. 112
Carefully monitor Ophthalon concentrations because high concentrations may occur and tend to increase with succeeding doses. 112 (See Pediatric Use under Cautions.)
Ophthalon is an antibacterial agent with a broad spectrum of activity against gram-positive bacteria, gram-negative bacteria, and Rickettsia. Its mechanism of action is by inhibition of bacterial protein synthesis by binding with ribosomes.
The major toxicity of Ophthalon is hematological. 9 In all vertebrates studied, it produces direct, dose-dependent bone marrow depression resulting in reductions in red blood cells, white blood cells, and platelets. This manifestation is aggravated by inappropriate doses, extended treatments, and repeated use of the drug. Treatment of Ophthalon intoxication is supportive and may require blood transfusions. The drug has also been reported to be appetite suppressive. Like gentamicin, Ophthalon is being used less frequently as safer antibiotics become available. The recommended dosage for Ophthalon is 50 mg/kg IM (SC in snakes) administered once daily or every other day.
How is this medicine (Ophthalon) best taken?
Use Ophthalon as ordered by your doctor. Read all information given to you. Follow all instructions closely.
- It is given into a vein for a period of time.
What do I do if I miss a dose?
- Call your doctor to find out what to do.
What if I take too much?
Don't worry if a few more drops of Ophthalon accidentally fall into your eye or ear, or if you accidentally apply more of the ointment than you meant to.
If you or your child swallow Ophthalon ointment or drops, seek medical attention.
Like all medicines, Ophthalon can cause side effects, although not everyone gets them.
What Are Side Effects Associated with Using Ophthalon?
Common side effects of Ophthalon include:
- not enough red blood cells produced (aplastic anemia)
- bone marrow suppression
- inflammation of the small intestine and the colon (enterocolitis)
- accumulation of Ophthalon especially in newborns (gray syndrome)
- inflammation of the optic nerve
- weakness and numbness in your hands and feet
- inflamed and soremouth
This document does not contain all possible side effects and others may occur. Check with your physician for additional information about side effects.