
I'm not sure what it was (because it was years ago, and out in Canada in any case) but I have, once, used something to prevent a season (given right at the very start of a season to work) as I wanted to take her to an important show - and NOT in season. Only once, and I have since heard that this has been withdrawn because of adverse side effects. My bitch was fine however, but I only used this the one time.