Description:
Depo-Medrol, 20mg/ml, 20 ml
Pharmacia & Upjohn
Brand of methylprednisolone acetate
Sterile Aqueous
Suspension
20 mg per mL and 40 mg
per mL
For Use in Animals
Only
DESCRIPTION
These preparations are
recommended for intramuscular and intrasynovial injection in horses and dogs,
and intramuscular injection in cats. DEPO-MEDROL Sterile Aqueous Suspension is
available in two concentrations,. Each mL of these preparations contains:
|
|
20 mg |
40 mg |
|
Methylprednisolone
acetate |
20 mg |
40 mg |
|
Polyethylene
glycol 3350 |
29.6 mg |
29 mg |
|
Sodium chloride |
8.9 mg |
8.7 mg |
|
Myristyl-gamma-picolinium chloride added as preservative |
0.198 mg |
0.195 mg |
When necessary, pH was
adjusted with sodium hydroxide and/or hydrochloric acid.
METABOLIC AND
HORMONAL EFFECTS
Methylprednisolone, an
anti-inflammatory steroid synthesized and developed in the Research Laboratories
of The Upjohn Company, is the 6-methyl derivative of prednisolone. Exceeding
prednisolone in anti-inflammatory potency and having even less tendency than
prednisolone to induce sodium and water retention, methylprednisolone offers the
advantage over older corticosteroids of affording equally satisfactory
anti-inflammatory effect with the use of lower doses and with an enhanced split
between anti-inflammatory and mineralocorticoid activities. Estimates of the
relative potencies of methylprednisolone and prednisolone range from 1.13 to
2.1, with an average of 1.5. In anti-inflammatory activity, as measured by the
granuloma pouch assay, methylprednisolone is twice as active as prednisolone. In
mineralocorticoid activity (ie, the capacity to induce retention of sodium and
water in the adrenalectomized rat) methylprednisolone is slightly less active
than prednisolone. The duration of plasma steroid levels following rapid
intravenous injection in intact dogs is appreciably longer for
methylprednisolone than for prednisolone, the respective “half-life” value for
the two steroids being 80.9
±
7.5 minutes for methylprednisolone and 71.3
±1.7
minutes for prednisolone.
While the effect of
parenterally administered DEPO-MEDROL is prolonged, it has the same metabolic
and anti-inflammatory actions as orally administered methylprednisolone acetate.
INDICATIONS
Musculoskeletal
Conditions. As with other
adrenal steroids, DEPO-MEDROL Sterile Aqueous Suspension has been found useful
in alleviating the pain and lameness associated with acute localized arthritic
conditions and generalized arthritic conditions. It has been used successfully
to treat rheumatoid arthritis, traumatic arthritis, osteoarthritis, periostitis,
tendinitis, synovitis, tenosynovitis, bursitis, and myositis of horses;
traumatic arthritis, osteoarthritis, and generalized arthritic conditions of
dogs. Remission of musculoskeletal conditions may be permanent, or symptoms may
recur, depending on the cause and extent of structural degeneration.
Allergic
Conditions. This preparation is
especially beneficial in relieving pruritus and inflammation of allergic
dermatitis, acute moist dermatitis, dry eczema, urticaria, bronchial asthma,
pollen sensitivities and otitis externa in dogs; allergic dermatitis and moist
and dry eczema in cats. Onset of relief may begin within a few hours to a few
days following injection and may persist for a few days to six weeks. Symptoms
may be expected to recur if the cause of the allergic reaction is still present,
in which case retreatment may be indicated. In treating acute hypersensitivity
reactions, such as anaphylactic shock, intravenous SOLU-DELTA-CORTEF®
Sterile Powder containing prednisolone sodium succinate, as well as other
appropriate treatments, should be used.
Overwhelming
Infections with Severe Toxicity.
In dogs and cats moribund from overwhelmingly severe infections for which
antibacterial therapy is available (eg, critical pneumonia, pyometritis),
DEPO-MEDROL may be lifesaving, acting to inhibit the inflammatory reaction,
which itself may be lethal; preventing vascular collapse and preserving the
integrity of the blood vessels; modifying the patient's reaction to drugs; and
preventing or reducing the exudative reaction which often complicates certain
infections. As supportive therapy, it improves the general attitude of the
animal being treated. All necessary procedures for the establishment of a
bacterial diagnosis should be carried out whenever possible before institution
of therapy. Corticosteroid therapy in the presence of infection should be
administered for the shortest possible time compatible with maintenance of an
adequate response, and antibacterial therapy should be continued for at least
three days after the hormone has been withdrawn. Combined hormone and
antibacterial therapy does not obviate the need for indicated surgical
treatment.
Other Conditions.
In certain conditions where it is desired to reduce inflammation,
vascularization, fibroblastic infiltration, and scar tissue, the use of
DEPO-MEDROL should be considered. Snakebite of dogs also is an indication for
the use of this suspension because of its anti-toxemic, anti-shock, and
anti-inflammatory activity. It is particularly effective in reducing swelling
and preventing sloughing. Its employment in the treatment of such conditions is
recommended as a supportive measure to standard procedures and time-honored
treatments and will give comfort to the animal and hasten complete recovery.
CONTRAINDICATIONS
Systemic therapy with
methylprednisolone acetate, as with other corticoids, is contraindicated in
animals with arrested tuberculosis, peptic ulcer, and Cushing's syndrome. The
presence of active tuberculosis, diabetes mellitus, osteoporosis, renal
insufficiency, predisposition to thrombophlebitis, hypertension, or congestive
heart failure necessitates carefully controlled use of corticosteroids.
Intrasynovial, intratendinous, or other injections of corticosteroids for local
effect are contraindicated in the presence of acute infectious conditions.
Exacerbation of pain, further loss of joint motion, with fever and malaise
following injection may indicate that the condition has become septic.
Appropriate antibacterial therapy should be instituted immediately.
WARNING
Clinical and
experimental data have demonstrated that corticosteroids administered orally or
parenterally to animals may induce the first stage of parturition when
administered during the last trimester of pregnancy and may precipitate
premature parturition followed by dystocia, fetal death, retained placenta and
metritis.
Additionally,
corticosteroids administered to dogs, rabbits, and rodents during pregnancy have
resulted in cleft palate in offspring. Corticosteroids administered to dogs
during pregnancy have also resulted in other congenital anomalies, including
deformed forelegs, phocomelia, and anasarca.
Not for human use.
PRECAUTIONS
DEPO-MEDROL Sterile
Aqueous Suspension exerts an inhibitory influence on the mechanisms and the
tissue changes associated with inflammation. Vascular permeability is decreased,
exudation diminished, and migration of the inflammatory cells markedly
inhibited. In addition, systemic manifestations such as fever and signs of
toxemia may also be suppressed. While certain aspects of this alteration of the
inflammatory reaction may be beneficial, the suppression of inflammation may
mask the signs of infection and tend to facilitate spread of microorganisms.
Hence, all patients receiving this drug should be watched for evidence of
intercurrent infection. Should infection occur, it must be brought under control
by the use of appropriate antibacterial measures, or administration of this
preparation should be discontinued. However, in infections characterized by
overwhelming toxicity, methylprednisolone acetate therapy in conjunction with
appropriate antibacterial therapy is effective in reducing mortality and
morbidity. Without conjoint use of an antibiotic to which the invader-organism
is sensitive, injudicious use of the adrenal hormones in animals with infections
can be hazardous. As with other corticoids, continued or prolonged use is
discouraged.
While no sodium
retention or potassium depletion has been observed at the doses recommended,
animals receiving methylprednisolone acetate, as with all corticoids, should be
under close observation for possible untoward effects. If symptoms of
hypopotassemia (hypokalemia) should occur, corticoid therapy should be
discontinued and potassium chloride administered by continuous intravenous drip.
Since this drug lacks
significant mineralocorticoid activity in usual therapeutic doses, it is not
likely to afford adequate support in states of acute adrenocortical
insufficiency. For treatment of the latter, the parent adrenocortical steroids,
hydrocortisone or cortisone, should be used.
INTRAMUSCULAR
ADMINISTRATION AND DOSAGE
Following
intramuscular injection of methylprednisolone acetate, a prolonged systemic
effect results. The dose varies with the size of the animal patient, the
severity of the condition under treatment, and the animal's response to therapy.
Dogs and Cats.
The average intramuscular dose for dogs is 20 mg. In accordance with the size of
the dog and severity of the condition under treatment, the dose may range from 2
mg in miniature breeds to 40 mg in medium breeds, and even as high as 120 mg in
extremely large breeds or dogs with severe involvement.
The average
intramuscular dose for cats is 10 mg with a range up to 20 mg.
Injections may be made
at weekly intervals or in accordance with the severity of the condition and
clinical response.
Horses.
The usual intramuscular dose for horses is 200 mg repeated as necessary.
For maintenance
therapy in chronic conditions, initial doses should be reduced gradually until
the smallest effective (ie, individualized) dose is established. MEDROL®
Tablets containing methylprednisolone may also be used for maintenance in dogs
and cats, administered according to the recommended dose.
When treatment is to
be withdrawn after prolonged and intensive therapy, the dose should be reduced
gradually.
If signs of stress are
associated with the condition being treated, the dose should be increased. If a
rapid hormonal effect of maximum intensity is required, as in anaphylactic
shock, the intravenous administration of highly soluble SOLU-DELTA-CORTEF®
Sterile Powder containing prednisolone sodium succinate is indicated.
INTRASYNOVIAL
ADMINISTRATION AND DOSAGE
Methylprednisolone
acetate, a slightly soluble ester of methylprednisolone, is capable of producing
a more prolonged local anti-inflammatory effect than equimolar doses of
hydrocortisone acetate. Following intrasynovial injection, relief from pain may
be experienced within 12 to 24 hours. The duration of relief varies, but
averages three to four weeks, with a range of one to five or more weeks.
Injections of methylprednisolone acetate have been well tolerated. Intrasynovial
(intra-articular) injections may occasionally result in an increased localized
inflammatory response.
Intrasynovial
injection is recommended as an adjuvant to general therapeutic measures to
effect suppression of inflammation in one or a few peripheral structures when
(1) the disease is limited to one or a few peripheral structures; (2) the
disease is widespread with one or a few peripheral structures actively inflamed;
(3) systemic therapy with other corticoids or corticotropin controls all but a
few of the more actively involved structures; (4) systemic therapy with
cortisone, hydrocortisone, or corticotropin is contraindicated; (5) joints show
early but actively progressing deformity (to enhance the effect of physiotherapy
and corrective procedures); and (6) surgical or other orthopedic corrective
measures are to be or have been done.
The action of
DEPO-MEDROL Sterile Aqueous Suspension injected intrasynovially appears to be
well localized since significant metabolic effects characteristic of systemic
administration of adrenal steroids have not been observed. In a few instances
mild and transient improvement of structures other than those injected have been
reported. No other systemic effects have been noted. However, it is possible
that mild systemic effects may occur following intrasynovial administration, and
this possibility is greater the larger the number of structures injected and the
higher the total dose employed.
Procedure for
Intrasynovial Injection. The
anatomy of the area to be injected should be reviewed in order to assure that
the suspension is properly placed and to determine that large blood vessels or
nerves are avoided. The injection site is located where the synovial cavity is
most superficial. The area is prepared for aseptic injection of the medicament
by the removal of hair and cleansing of the skin with alcohol or Mercresin®
tincture. A sterile 18- to 21-gauge needle for horses, 20- to 22-gauge needle
for dogs, on a dry syringe is quickly inserted into the synovial space and a
small amount of synovial fluid withdrawn. If there is an excess of synovia and
more than 1 mL of suspension is to be injected, it is well to aspirate a volume
of fluid comparable to that which is to be injected. With the needle in place,
the aspirating syringe is removed and replaced by a second syringe containing
the proper amount of suspension which is then injected. In some animals a
transient pain is elicited immediately upon injection into the affected cavity.
This pain varies from mild to severe and may last for a few minutes up to 12
hours. After injection, the structure may be moved gently a few times to aid
mixing of the synovial fluid and the suspension. The site may be covered with a
small sterile dressing.
Areas not suitable for
injection are those that are anatomically inaccessible such as spinal joints and
those like the sacroiliac joints, which are devoid of synovial space. Treatment
failures are most frequently the result of failure to enter the synovial space.
If failures occur when injections into the synovial spaces are certain, as
determined by aspiration of fluid, repeated injections are usually futile. Local
therapy does not alter the underlying disease process, and whenever possible
comprehensive therapy including physiotherapy and orthopedic correction should
be employed.
The single
intrasynovial dose depends on the size of the part, which corresponds to the
size of the animal. The interval between repeated injections depends on the
duration of relief obtained.
Horses.
The average initial dose for a large synovial space in horses is 120 mg with a
range from 40 to 240 mg. Smaller spaces will require a correspondingly lesser
dose.
Dogs.
The average initial dose for a large synovial space in dogs is 20 mg. Smaller
spaces will require a correspondingly lesser dose.
HOW SUPPLIED
DEPO-MEDROL Sterile
Aqueous Suspension, 20 mg/mL, is available in 10 mL and 20 mL vials, and 40 mg/mL
is available in 5 mL vials.
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