Understanding Adverse Vaccine Reactions

When a vaccine reaction occurs, out first reaction is usually one that we relate directly to the drug itself or the manufacturer. One part of the puzzle is an over exposure to that specific allergen which causes the body to work overtime to fight. Each manufacturer provides for the safe frequency of the vaccine, but like humans, there are always individual differences. You can check titer levels, but the results are not accurate enough to make informed decisions as of yet. The other part of the puzzle is that it could be a bad batch.

While a vaccine is approved to be given annually, there is a chance that there is still enough of the allergen in the body providing protection, thus the additional vaccine in a sense is an overdose, sending the body into turmoil. With no way of truly knowing the levels before hand, it is a chance we must take. If a severe reaction does occur, future consideration of vaccinating with the same drug should be strongly considered and discussed with your veterinarian. Usually the severity of the reaction and the option of alternatives will be the deciding factor. Vaccine reaction rates are calculated as follows: If you have 4 ferrets that are 4 years old that is 16 vaccines (4 for each ferret). During their first year they each received their booster shots (3 each) so that's another 12 vaccines for a total of 28. If 1 ferret has a reaction, the rate is 3.57%.

Anaphylactic shock will generally begin with your ferret gagging, have difficulty breathing, and their tongue and skin could turn blue. They can also throw up, experience loss of bowel movement, pass blood in their urine and feces, go totally limp and unfortunately lapse into a coma and die. All of these signs and symptoms can occur within minutes and even seconds, and your veterinarian will need to administer emergency care immediately, which is why it is vital to remain at the vets office and keep a close eye on them. Your veterinarian will generally very quickly administer injectable benedryl, epinephrine (which literally will jump start their heart/body) and supply them with oxygen. This procedure will generally repeat until your ferret begins responding and stabilizes. Once your ferret is stabilized and released to go home, it is equally important to keep a very close eye on the ferret to ensure there are no repeat episodes and don't slip into a coma. They will be very lethargic due to all the emergency care and injections they have received.

Though often overlooked, it can never be stressed how important it is to report any and all adverse event your ferret,or any pet, may have to medication. Unlike with humans, there is no legal requirement for veterinarians to report adverse events. It has been reported that some veterinarians who have attempted to contact the FDA, have been given a slew of different numbers to contact to report the event, only to end of back to the same number where they started. Another obstacle is figuring out which form(s) to complete and where to send them.

Any and all adverse events should be made to the actual drug manufacturer. It is also highly recommended, that the events be reported to the correct government agencies responsible for collecting the information and following up. Through these reports, the manufacturer can access whether the drug needs to be reformulated, modify route of administration, modify how the drug should be given, determine any contraindications, etc. The reporting procedure does not change if the drug is used off-label (most drugs for animal use are), or is a human drug (a large percentage is).

The US Food and Drug Administration Center for Veterinary Medicine has published a brochure explaining the Adverse Drug Event Reporting System and why participation is important. Available for download.

Below you will find additional information on how to report adverse drug events