Guidelines for Treating Ocular Inflammation with Steroids
When prescribing topical steroids, choose the drug, dosage
and frequency of administration based on the severity of the
inflammation. Acute inflammatory conditions, most notably anterior
chamber inflammatory reactions, are best managed aggressively
(one drop every waking hour) until the inflammation is under
control.
Don’t automatically fall into the four-times-a-day routine,
since in most cases this can leave the condition undertreated.
As with any treatment, tailor the dosage to the specific presentation
at hand.
Accurate diagnosis is crucial before prescribing any drug,
but it’s particularly important with steroids. There are three
instances in which we would NOT consider using steroids by
themselves, although it may be appropriate to use a steroid-antibiotic
combination:
1. Avoid steroids when treating an acute
bacterial or fungal infection, mainly because steroids do
not possess antimicrobial properties. Steroids can also mask the infection, making the
eye look white and feel better but doing nothing to address
the underlying infection. An exception is a case where there
is concurrent secondary inflammation. Here, a combination product
like TobraDex will eradicate the bacteria and concurrently
quiet the inflammatory expression.
2. Steroids are contraindicated when
there is a significant corneal epithelial defect. The corneal epithelium is a critical
barrier to bacterial invasion, so it’s usually best to wait
until the epithelium is intact before starting steroid therapy.
Steroids may initially mute epithelial healing and invite secondary
bacterial infection. An exception to this rule is when there
is significant inflammation of the epithelial or stromal tissues.
Then, use of a combination antibiotic/steroid drug may be helpful—perhaps
even essential—in achieving tissue healing.
3. Steroids are contraindicated when
you’re unsure of the diagnosis. Since some inflammatory conditions are “non-specific,”
it’s better to prescribe a steroid-antibiotic combination in
these cases. If the slit lamp picture defies precise diagnosis—and
you’ve ruled out herpes simplex keratitis, bacterial infection
or a large epithelial defect—it’s generally OK to treat with
a steroid. In such cases, use a combination drug such as TobraDex.
One of the greatest problems we see among doctors is undertreatment
with steroids. Remember, your goal is to restore normal tissue
integrity as quickly as possible. Use steroids aggressively
for the first few days until the inflammation is brought under
control. Then, and only then, should you begin the tapering
process. High doses of steroids over a short term of several
days are almost always safe and effective. It is generally
in protracted care (beyond three to four weeks of intensive
therapy) where the risk of complications increases.
If steroids are used for a week or less, it is not absolutely
necessary to taper them. But in general, when we prescribe
steroids, we will taper them even if used for less than a week.
After a few weeks of therapy (which is rarely indicated), tapering
gives the body time to adjust its mechanism for producing the
natural steroids hydrocortisone and corticosterone.
Tapering also avoids the inflammatory rebound effect that
can result when you discontinue steroids abruptly. A good rule
of thumb is to taper the dosage frequency by half for each
given time interval once the inflammation is controlled. For
example: q1h for 2 days , qid for 3 days, bid for 3 days.
Be especially aggressive when treating iritis. For a moderate
to severe iridocyclitis, for example, initiate Pred Forte 1%,
one drop q1h usually for 2 to 5 days or until the anterior
chamber reaction is well controlled, then start the tapering
process.
While treating a patient with steroids, it’s also important
to monitor the intraocular pressure for the rare side effect
of ocular hypertension. The truth is that side effects are
extremely uncommon when steroids are used short term, for two
weeks or less. Fortunately, almost all primary care conditions
respond in less than two weeks, and often less than one. Also,
bear in mind that post-PRK patients may use steroids for one
to three or more months with no reported steroid-induced side
effects.
In general, any time a patient uses a steroid for more than
a week or two, be sure to monitor the IOP frequently. Pressure
increase is due to decreased outflow through the trabecular
meshwork. If the pressure is high enough long enough, optic
nerve head damage can develop. However, it is also important
to remember that healthy optic nerves can endure pressures
into the high 20s or low 30s for a few weeks without any measurable
damage to structure or function.
If IOP does rise to a level of concern during the course of
therapy, there are three easy approaches:
1. If inflammation is under control and the tapering process
has begun, the IOP will usually self-limit as less steroid
is instilled. In most cases, proper tapering is all that is
required.
2. If inflammation is improving, yet requires therapy for
several more days, switch to loteprednol etabonate 0.5% for
the remainder of the therapy.
3. Add a glaucoma drug such as a beta-blocker, an alpha adrenergic
agonist or topical CAI until the IOP level is acceptable.
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