Drug of choice for treating tick-borne disease and heartworm is unavailable (or unaffordable) due to supply bottleneck.
When my newest search and rescue partner, Cole, fell apart during a certification test in May 2012, I had accumulated enough hard lessons to know my next move. We didn’t need to revisit our training protocol or take his nose in for a tune-up. We were at our vet’s office the next morning for bloodwork.
I left with a scrip for doxycycline, the drug of choice to treat Lyme disease in both humans and dogs. When I filled it at the Giant Eagle pharmacy, my bill was $0, thanks to the chain’s program of free prescriptions for common generic antibiotics. Many other pharmacy chains offered it for loss-leader prices ranging from $1.99 to $10. At average retail prices, the cost would have topped out at about 30 cents per pill, or $16 for the full course.
Cole was a lucky boy. His infection was detected very early, and he responded so well to treatment that his titer is negative a year later. Cole’s owner was lucky for those reasons, and because the specific drug that best treats Lyme disease, among other tick-borne infections such as ehrlichiosis, Rocky Mountain spotted fever, and anaplasmosis was readily and cheaply available.
Just under a year later, Pittsburgh, Pennsylvania dog owner Karen Kirk and her Lab/Husky-mix, Buddy, were less fortunate.
Buddy’s cryptic symptoms appeared suddenly in late March 2013; what first appeared to be a sprained hock developed rapidly over 24 hours into a critical situation, including complete hind-end paralysis and lethargy. Knowing that Buddy had several recent tick exposures, Kirk opted to run a tick-borne disease titer panel before taking radiographs; her hunch was also on target, as Buddy too returned a positive test for Lyme disease infection.
Kirk’s veterinarian prescribed a very high dose of doxycycline because of Buddy’s severe acute symptoms, and provided an initial supply of the drug, warning Kirk that there appeared to be an issue with acquiring the antibiotic, and that she should be ready to seek it at an outside pharmacy to continue the course.
Two weeks later, when Kirk called her local Giant Eagle pharmacy, the pharmacist’s assistant looked up the cost of Buddy’s prescribed dose and told her “This can’t be right. It says $1,000.”
After repeated checking, the pharmacy staff verified that the cost of Buddy’s prescription had skyrocketed to nearly $12 per pill, or $72 per day of treatment – for a staple generic drug that was so cheap 10 months earlier that they had been giving it away.
The news was no better at other Pittsburgh-area pharmacies; most simply could not supply doxycycline at any price. Buddy, who had responded to doxycycline treatment dramatically and was walking within 24 hours of his first dose, finally caught a break. Kirk’s veterinarian was able to scrounge enough of the drug at close to the pre-shortage price to complete a month of treatment. According to Kirk, “Now he’s acting like a badass like he always does, and propelling himself off the back of my couch.”
Veterinarians Scramble to Supply Treatments as Spring Tick Season Commences
According to the United States Food and Drug Administration (FDA) online index of drug shortages, the supply interruption for doxycycline was first noted in mid-January, and projected to be corrected by early March. As of mid-April, the listing showed only four extant manufacturers, of which two were supplying “limited” quantities and/or forms of the drug, and two were listing the drug as “available.” The reasons for the supply issues were listed, variously, as “manufacturing delays” and “increased demand.” As of April 10, FDA personnel had not returned multiple phone messages requesting an interview, and the FDA had released no further information about the causes and expected duration of the shortage.
While the shortage of this common antibiotic affects human medicine – where doxycycline is used to treat tick-borne diseases, acne, some sexually transmitted infections, and even anthrax – veterinarians are keenly aware of the pinch, as veterinary practices serve as pharmacies as well as physicians for their animal patients.
Dr. Dan Murray, who practices at the Animal Care Center in Green Valley, Arizona, has not yet exhausted his clinic’s supply of oral doxycycline, and continues to dole it out to patients on an as-needed basis. Anticipating that he will not be able to restock, Dr. Murray has ordered minocycline, a related tetracycline-class antibiotic, to replace doxycycline for the tick-borne ehrlichiosis and anaplasmosis that he commonly sees in southern Arizona, as well as for treating kennel cough.
But veterinarian Tom Beckett of the Camino Viejo Animal Clinic in Austin, Texas cautions that, although minocycline is in the same class as doxycycline, it has not yet been shown to be equally effective against the same rickettsial diseases, or as a pre-treatment for dogs who will undergo heartworm treatment. Dr. Beckett is also drawing from a stockpile of doxycycline at this time, and worries “I’m at a loss, like everybody else, about what we’re going to end up doing, how cheap and available the minocycline is going to be.” Dr. Beckett has a special interest in tick-borne diseases, which are enzootic among the former racing greyhounds that he helps to rehabilitate; both efficacy and cost are factors for this population of dogs.
A web search for minocycline prices found a best price of $1.70 per 100 mg tablet – six times higher than a typical price for doxycycline prior to the current shortage.
One reason for doxycycline’s effectiveness against notoriously recalcitrant bacterial infections such as Borrelia burgdorferi (the spirochete bacterium that causes Lyme disease) and the rickettsial bacteria that cause Rocky Mountain Spotted Fever, anaplasmosis, and ehrlichiosis, is its high lipid solubility, which allows it to attack pathogens that have set up shop in the central nervous system and in the synovial fluid of the joints. Minocycline has an even higher lipid solubility; human clinical results suggest that it should prove a suitable, if expensive, alternative to doxycycline for treating tick-borne diseases.
Readers who handle shelter dogs or others who are heartworm positive may also need to turn to minocycline or the older drug tetracycline for the 30-day antibiotic treatment prior to administering an adulticide to kill heartworms. The aim of this pre-treatment is to gradually eliminate the symbiotic rickettsial Wolbachia bacteria from the guts of the parasitic worms, preventing a toxic bolus of dead Wolbachia from overwhelming the treated dog’s cardiovascular system.
The Dangers of Hoarding and Stockpiling
Consumers must exercise caution when using stockpiled doxycycline, or any drug of the tetracycline group. All sources agree that antibiotics of this family that are long past their expiration dates are not only ineffective, but can break down into toxic substances that cause severe kidney damage.
Unfortunately, no sources can or will specify how far past the manufacturer’s expiration date is cause for concern, even though there is wide agreement that these dates are broadly, even excessively, conservative, and that “just expired” product is almost certainly safe and effective. Dr. Beckett cautions that variations in storage conditions – antibiotics should be kept cool and dry – are a confounding factor in shelf life. Ensure that you acquire antibiotics of this family only from reliable sources.
Heather Houlahan is the proprietor of First Friend Dog Training and raises pastured livestock and poultry. She has been a search and rescue dog handler for 22 years, and is the canine director of Allegheny Mountain Rescue Group. She lives with three English shepherds, one German shepherd, a revolving cast of foster dogs from National English Shepherd Rescue, and a mostly housetrained husband on Brandywine Farm, north of Pittsburgh, PA. She has had Lyme disease twice.
For more information:
– FDA Drug Shortage Index: http://www.fda.gov/Drugs/DrugSafety/DrugShortages/ucm314739.htm
– Doxycycline shortage and shelter medicine:
sheltermedicine.com/documents/addressing-the-doxycycline-shortage-feb-2013
– Heartworm: critterology.com/articles/wolbachia-and-their-role-heartworm-disease-and-treatment
– Minocycline treatment in humans with neurologically involved Lyme disease: http://cid.oxfordjournals.org/content/30/1/237.2.full
