Home beer brewing has become a popular hobby. Home brewing typically uses hops (Humulus) as part of the beer making process. While it is a fun hobby for beer enthusiasts, many people are unaware of the toxicity to dogs. While beer itself has its intoxicating effects from the alcohol, ingestion of hops before or after the brewing process can be lethal to your dog.
While the exact toxin and mechanism of action is not fully understood, the biologically active compounds are thought to be what cause malignant hyperthermia (436). With this condition, the body's temperature suddenly rises to temperatures greater than 108 degrees fahrenheit. The body's cells can not tolerate temperatures this high, resulting in death.
From time of ingestion, symptoms can manifest within a few hours. If caught soon enough, vomiting, activated charcoal or gastric lavage can be utilized to prevent absorption. Some breeds of dogs seem to be more sensitive than others to developing malignant hyperthermia. Dantrolene sodium can also be used to try and reverse the malignant hyperthermia. However, this drug is not commonly used in veterinary medicine, so most clinics do not have this drug on hand.
So, the take home message, it is better to make sure your pet does not have access to compost piles that may contain used hops or to the unused pellets or other forms of hops. If your pet does get into hops contact an emergency facility to make sure they have Dantrolene on hand. If not available, which is typically the situation, then supportive care to try and keep the body temperature from rising to critical levels is the goal.
Osweiler, Gary et al. Blackwell's Five Minute Veterinary Consult Clinical Companion Small Animal Toxicology. Blackwell Publishing 2011.