Transcript What is the Extent of Safety and Efficiency of Drug

What is the Extent of Safety and
Efficiency of Drug Desensitization on
Patients with Allergic Reactions?
Cindy Law
Dr. Mary Lee-Wong
What are Allergies?
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An abnormal sensitivity
to an allergen that is
inhaled, eaten, or
touched
An overreaction of a
hypersensitive immune
system
Misidentification of a
harmless substance as
harmful
Common Types of Allergies
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Allergic rhinitis
Food
Medication
Insect stings
Latex
chemical
Allergies and the Immune System
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B-lymphocytes &Tlymphocytes
Lymphocytes identifies
a foreign invader
Foreign antigens cause
production of antibodies
5 types of
immunoglobulins
Mast Cells and Basophils
Allergy Cascade
Anaphylaxis
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Severe allergic reaction
prominent in dermal and
systemic signs
Common causes are food,
medication, insect stings,
and latex
symptoms may begin in as
little as five to 15 minutes to
up to two hours after
exposure to the allergen
EpiPen
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epinephrine is a synthetic
version of a naturally
occurring hormone also
known as adrenaline
causes rapid constriction of
blood vessels, reversing
throat swelling, relaxing lung
muscles to improve
breathing, and stimulating
the heartbeat.
Allergy Tests
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Scratch test
Diluted extract of the
possible allergen to the
back or arm
Scratching the skin with
the needle
Blood tests
Places and Symptoms of Reactions
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The sensitized immune
system produces
antibodies against
allergens which cause
the release of
histamines into
bloodstream
Treatments
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Avoidance
Medication
Immunotheraphy
The injections help the immune system to
produce fewer IgE antibodies, while also
stimulating the production of a blocking
antibody IgG
Drug Desensitization
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Drug Desensitization allows safe delivery of
an antibiotic to a patient which has an IgE
medicated sensitivity to the drug by
administering it in small doses until a full
therapeutic dose is clinically tolerated
The procedure entails risk of acute allergic
reactions, including death
Drug Desensitization Protocols
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1.
Skin test patient to determine degree of sensitivity:
a. Dilute available drug solutions/suspension to 1/3 mg/ml.
b. Prepare three tenfold dilutions.
c. Perform prick-puncture testing with 1:1000 dilution
d. If negative, serial intradermal tests (0.02 ml [2-4mm bleb] in
duplicate) up to and including 3 mg/ml stock; discontinue testing when
>8 m wheal is observed. Test is positive if both duplicate wheals
increase significantly (>2-3 mm) 20 min after placement compared
with diluent control.
2. Prepare sufficient quantities of drug solution/suspension for
desensitization regimen in half-log 10 dilutions (threefold and tenfold
dilutions from
concentrate [1-3 mg/ml]).
Protocol Cont’d
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1. Establish baseline monitoring of patient in medical setting
appropriate for patient's clinical conditions and the nature and
severity of the prior reaction.
Start a secure intravenous infusion.
2. Starting dose: If skin test negative and test is unvalidated,
begin with 0.1 ml of 1/3 microgram/ml solution/suspension; if
skin test positive, begin 100-fold below the dose producing a
midpint (5-8 mm wheal) reaction.
3. Route; oral by ingestion or ng tube in 30 ml water;
parenteral by intradermal (<0.2 ml), SC (0.2-0.6 ml), or
intramuscular (>0.6 ml) injection.
Protocol Cont’d
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4. Dosing interval: 15-20 min for parenteral doses; 20-30 min
for oral dosing. Repeat dose for mild systemic reaction: drop
back two doses (tenfold) for moderate reactions, further for any
reactions producing hemodynamic changes.
5. Dose escalation; half-log 10 (-threefold) increments; e.g., 1
g, 3 g, 10 g, 30 g, 100 g, etc.
6. If IV therapy is indicated, begin infusion to deliver a dose
equivalent to the last oral/parenteral dose slowly over 1 hour.
Double the infusion rate every
hour until target therapeutic dosing is achieved.
Penicillin Drug Desensitization
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Background:
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A 32 year old female is pregnant and is
diagnosed with syphilis
Penicillin is the ideal antibiotic to treating
The mother is allergic to penicillin
Her obstetric history included one vaginal delivery
at term and four subsequent spontaneous
abortions at 12 to 16 weeks.
Bibliography
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.Sullivan TJ. Drug Allergy. In: Midleton E, Jr. ed. Allergy, principles, and practice. 4th ed. St. Louis: CV Mobsby Co, 1993: 1725-1746
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.Ohman JL, Jr. Clinical and immunologic responses to immunotherapy. In: Lockey RF, Bukantz SC, eds. Allergen immunotheraPY. New York: Marcel Decker,
Inc, 1991: 209-232
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.Yunginger JW. Insect Allergy. In: Midleton E, Jr, ed. Allergy, principles, and practice. 4th ed. St. Louis: CV Mobsby Co, 1993: 1511-1514
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.Patterson R, De Swarte RD, Greenberger PA, et al. Drug Allergy and protocols for mangement of drug allegies. N Engl Reg Allergy Proc 1986; 7: 325.
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.In: The extra pharmacopoeia. 29th ed. London: The Pharmaceutical Press, 1989, 1189-1195
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.Monaghan MS, Glasco G, et al. Safe administration of iron dextran to patient who reacted to the test dose. South Med J 1994: 87(10): 1010-1012
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.Novey HS, Pahl M, Haydik Y, Vaziri ND, Immunologic studies of anaphylaxis to iron destran in patients on renal dialysis. Ann Allergy 1994; 72(3): 224-228
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.Patterson R, De Swarte RD, Greenberger PA, et al. Drug Allergy and protocols for managements to drug allergies. Allergy Proc (Spanish edition)
1995;9(2):13
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.Bridges KR, Bunn HF. Anemias with distributed iron metabolism. In: Isselbacher KJ, Braunwald E, Wilson JD, et al, eds. Harrison’s. Principles of internal
medicine. 13th ed. McGraw-Hill, 1994; 1721-1723
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.Patterson R, De Swarte RD, Greenberger PA, et al. Drug Allergy and protocols for managements to drug Allergies. N Engl Reg Allergy Proc 1986; 7: 325342
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.Sullivan TJ, Yecies LD, Shats GS, et al. Desensitization of patients allergic to penicillin using orally administered beta-lactam antibiotics. J Allergy Clin
Immunol 1982; 69:275-282
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.Stark BJ, Earl HS, Gross GN, et al. Acute and chronic desensitization of penicillin. J Aallergy Clin Immunol 1987; 79: 523-532
Special Thanks to:
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Harlem Children Society
Dr. Sat
Dr.Mary Lee-Wong
Beth Israel Medical Center