ALLERGY SHOTS (IMMUNOTHERAPY)

Dr. Bruce Sweet 2013

1. Allergy shots are given in the mid portion of the upper arm subcutaneously (halfway between the surface of the skin and the underlying muscle).

2. Regular allergy shots are given weekly for the first 3 to 4 months. (This can take longer if you are very sensitive to your shots.) After this initial phase shots are given monthly (maintenance dose) for a period of five years or more. Every effort must be made to get your shots regularly as this improves the effectiveness of this treatment. Short pre-seasonal shots (usually 8) can be given yearly, prior to the start of certain specific pollen seasons, but results in less effective long-term improvement than regular year-round shots.

3. Each allergy shot tends to sting for several minutes and then often causes soreness-itching, redness, and swelling for two days (local reaction). Increasing size of local reactions or any non local symptoms caused by your allergy shots must be reported to your doctor before your next shot.

4. AFTER EVERY ALLERGY SHOT, YOU MUST STAY IN THE DOCTORS OFFICE FOR 20 TO 30 MINUTES to ensure there is no immediate severe reaction to your shot. You cannot eat or exercise vigorously for 2 hrs. after an allergy shot (no hot tub-sauna, etc.). Water, coffee, and tea are fine.

5. Major / immediate / serious reactions usually occur within 30 minutes of the allergy shot being given. These reactions consist of one or more of the following: generalized itching (esp. under chin or arms, face), numbness of lips or face or hands, difficulty breathing or wheezing, hives or skin rash, feeling faint, headache, cramps, fatigue. These reactions must be immediately treated.

6. Less commonly, delayed reactions similar to the above, can occur up to 12 hours after a shot, particularly with newer slow release allergy serums.

7. Mild allergy reactions are treated with an oral antihistamine such as: Reactine TM 10 mg, Allegra TM 60 mg, Claritin TM 10 mg, Aerius TM 5mg. (Benadryl 50 mg or Chlortripolon 4 mg are not recommended anymore because of the sedation and impairment in motor performance and memory that they cause). More severe reactions require adrenalin/epinephrine (EPI-PEN TM) and treatment in an emergency department (intravenous, etc.). Antihistamines must be taken one to two hours prior to an allergy shot to reduce the chance of both serious and local reactions.

8. ABSOLUTE CONTRAINDICATIONS to getting an allergy shot include active poorly controlled asthma and a severe reaction to your last shot (until reassessed). Certain medications are usually contraindicated (i.e. Beta blockers such as metoprolol or atenolol (all end in “olol” , or ACE inhibitors such as enalapril, quinapril (all end in “pril”) used to treat high blood pressure and heart conditions) and I usually ask patients who are on these meds to take their morning dose at least 2 hours after their shots (never just before). NSAIs (nonsteroidal anti-inflammatories) such as ASA, ibuprofen (Advil, Motrin, etc.), diclofenac, Naprosyn, naproxen (Aleve,etc.), celecoxib (Celebrex), indomethacin, and others are generally contraindicated immediately prior to shots. Many individuals with allergies and asthma are sensitive to these medications but do not know it, and I have had several nasty reactions to immunotherapy in individuals who had taken an NSAI a couple of hours prior to getting their shots.

YOUR ALLERGY SHOTS CONTAIN SUBSTANCES YOU ARE ALLERGIC TO

A SERIOUS REACTION IS POSSIBLE WITH EVERY ALLERGY SHOT

Every year in North America millions of allergy shots are given and a few individuals have an acute anaphylactic reaction to their shots. Most of these severe/fatal reactions are avoidable by following the protocol above. However, these severe reactions can be unpredictable and can occur any time. Immunotherapy is a very effective and a very serious form of treatment. Many patients who have been on shots for several years (and never had a reaction) begin to take the shots “lightly” assuming a reaction cannot happen to them. I have had patients on shots for as long as ten years who have had a sudden and unpredictable major reaction. Immunotherapy is serious and the protocol above must always be followed.

Specific Notes for Local Patients Attending My Allergy Shot Clinic:

-this applies to individuals living in or near Thunder Bay that I personally give allergy shots to.

-routine times are Monday mornings from 7:00 to 9:30 a.m. (from end Aug. through May)).

(from June through August shots are given on specific days and patients are given a shot schedule)

-no appointment is necessary.

-always be prepared to wait 20 minutes after your shots prior to leaving the office – this is mandatory.

(you can have had shots for years with no reaction, and then develop a severe reaction)

-always take an antihistamine one hour prior to receiving your allergy shots – this is mandatory.

-having a cold/the flu or getting a blood test is not a contraindication to getting your regular allergy shots.

-if your allergies/asthma is very poorly controlled, allergy shots are normally not given, at least not at regular dose.

-you can have a normal breakfast prior to getting your shots BUT you cannot eat food, exercise vigorously, or have a sauna-hot tub for two hours after your shots. Water, coffee or tea is not a problem.

-when you are just starting your allergy shots you normally have your shots once a week for usually about 12-16 weeks prior to going on your monthly maintenance shots. Some patients will require their maintenance shots more frequently.

-patients receiving allergy shots for molds usually will get 2 shots at each visit (1 shot in each arm); one shot for molds and the other shot for all other allergens (pollens, pets, dust mites, etc.).

-for patients who are severely sensitive to their shots (get abnormally large long-lasting local reactions or get non-local symptoms) the shot schedule has to be modified and it will take much longer to get up to your maintenance dose. (However, take heart, as these individuals eventually have spectacular improvement in their allergy symptoms from the shots.)

STOPPING IMMUNOTHERAPY (ALLERGY SHOTS)

Note: Basic avoidance measures (dust free bedroom, pet control measures) must be continued for a lifetime. Not only do avoidance measures improve symptoms and decrease medication use, but, they decrease the drive on the allergy immune system, increase the effectiveness of immunotherapy, improve chances of eventually stopping immunotherapy, and enhance chances of allergies improving over time.

Preamble

Before discussing exactly when stopping allergy shots can be considered you have to understand basic process of immunotherapy. When beginning immunotherapy (whether it be for venoms, pollen, pets, dust mites, molds, etc.) you receive a very small initial dose that is gradually increased over a period of several months to a much higher maintenance dose. Your immune system when exposed to these increasing doses adapts in several ways including producing IgG blocking antibodies. Remember that allergies are caused by excessive production of IgE antibodies to a specific substance or substances. In essence another part of the immune system responds to immunotherapy and prevents the allergic IgE response. The individual undergoing immunotherapy becomes less sensitive to the specific allergens in the immunotherapy shot and in common terms becomes “desensitized”. If an individual’s immune system induces permanent IgG blocking antibodies you can stop immunotherapy and the person will continue to maintain desensitization. If an individual’s immune system does not produce permanent IgG blocking antibodies only temporary desensitization occurs and immunotherapy must be continued (at times indefinitely) to maintain this state of desensitization.

Studies looking closely at Hymenoptera venom desensitization have suggested that optimum desensitization occurs after five years of immunotherapy. Many of these individuals maintain permanent desensitization, although not all (and this raises a difficult question of exactly who should stop and who shouldn't; and stopping venom immunotherapy is a risk benefit decision to be made between allergist and patient). From my own experience with immunotherapy (involving pollens/pets/molds,dust mites,etc.) 30 years ago approximately 3 of 4 individuals (75%) who had been on immunotherapy for three years could discontinue immunotherapy and be fine for many years before any evidence of allergies recurred. However, in the last 10 years I estimate that approximately 3 of 4 individuals (75%) who had been on immunotherapy for five years cannot stop their shots without their allergies getting significantly worse. In other words in the last 10 years far fewer individuals attain permanent desensitization. The reason for this change is unknown but clearly is related to our present environment. One clue to this is the steadily increasing carbon dioxide concentration in the air which is causing both plants to produce more pollen and mold to produce more spores (literally we have more allergen in the air). Another clue lies in the fact that our immune systems are being bombarded by more and more foreign particles/chemicals/pollutants. For example, we know that diesel exhaust particles can combine with allergens in the air to make them more allergenic (induce a more severe allergic response in an individual than the allergen would on it’s own) and we know that these diesel exhaust particles also directly increase allergic inflammation in respiratory lining. I am sure there are many more particles/chemical/pollutants that are stimulating our immune system (remembering that allergies represent an overactivity of the immune system and things that stimulate our immune system in general could theoretically make allergies worse).

Specific Questions Regarding Stopping Immunotherapy for Common Allergens (NOT for venoms)

1) How long you been on immunotherapy?

Minimum recommended is usually 5 years.

2) What sort of local reaction have you been getting to your immunotherapy?

If you have been having no redness, swelling, or itching of any kind from your immunotherapy it makes it more likely you have induced long term desensitization and can stop your shots.

3) Have your allergy symptoms completely disappeared?

For example, if you have been getting allergy shots for seasonal hayfever have your symptoms completely disappeared during that season and do you require any seasonal medication? If there are no symptoms and no meds are required it is more likely you can stop your shots. Similarly, if you are given shots for pet allergen and exposure to pets causes no symptoms whatsoever, you likely can try to stop your shots.

4) How do you feel between your maintenance allergy shots?

If you have been getting maintenance shots monthly and find you have no allergy symptoms, consider extending the time period between maintenance shots prior to considering stopping your shots. However, if you still feel that your allergies get worse prior to your next maintenance shot(s) or if you miss an allergy shot or two and your allergies get worse (and subsequently get better when you have another shot) you very likely will have to continue your shots. Note: if you find your allergies are getting worse while you're on immunotherapy this means that you are developing new allergies and retesting is appropriate.

If the answers to the above questions all suggest you can stop your shots it is definitely worthwhile discussing this with your Dr.

Three scenarios are possible. Your allergies might significantly worsen over the next several months after stopping your shots. Your allergies might gradually worsen over a period of two or three years after stopping. Your allergies may be improved for decades (but can worsen eventually). With all three of these scenarios, retesting is usually indicated prior to considering instituting more immunotherapy.

Dr. Sweet 2013