Problems with Parasites and Praziquantel
October 15, 2000 4 minutes read
Problems with Parasites and Praziquantel
Case Report
Synopsis: A consultation for tapeworm infestation leads to the discovery that praziquantel is only being supplied in limited quantities.
A 42-year-old asian indian man was recently referred to me for evaluation of tapeworm infestation. He had immigrated to the United States from India in 1988, working—like almost everyone else in Silicon Valley these days—as a software engineer. He was diagnosed with chronic myelogenous leukemia in 1991, and underwent successful bone marrow transplantation. He had not been back to India for eight years. He had done extremely well until a few weeks earlier when he noticed a long white object in the toilet bowl. Fishing it out with a stick—and nearly giving his poor wife a heart attack in the process—he determined that it was about 5 feet in length, opaque-white, with numerous small segments. He then carefully placed it back in the bowl, and flushed it.
Upon contacting his internist, he was promptly referred to me for an Infectious Disease consultation. I thought this was going to be a slam-dunk. In fact, I thought it was an unnecessary consultation, assuming any good internist could treat a tapeworm.
When the patient came to my office several days later, he was armed with an exhaustive list of questions, including the age of the worm, its species, how it obtained nutrients, etc. By now, he’d had access to the internet, and knew more about tapeworms than I ever hope to. His major concern was autochtonous infection. Ninety minutes later, the patient was mostly satisfied, and I scribbled out a prescription for a single 600 mg dose of praziquantel (Biltricide, Bayer Pharmaceutical), ordered three stool O & P, and wished him well.
Comment by Carol A. Kemper, MD, FACP
It was there that the trouble really began. Seldom has such a seemingly straightforward consultation been such a problem! A flurry of phone calls later, it was determined that not a single pharmacy in our area carried praziquantel tablets including Rite-AID, Walgreen’s, Longs Drug, and two hospital pharmacies. We were repeatedly told that it was "unavailable." Further inquiry revealed that Bayer was no longer distributing praziquantel tablets. I finally located several tablets but they were a year out of date and the pharmacist refused to dispense them. What to do? According to the Medical Letter, praziquantel is considered the first-line agent for intestinal tapeworms. Albendazole does not have sufficient intraluminal activity and is not recommended. I quickly learned that niclosamide (nicloside), the alternate agent, was also unavailable.
Finally, much to my delight, the pharmacist at our HMO-based clinic got on the web and learned that biltricide compound, which is routinely used by veterinarians, was readily available, and downloaded a "recipe" for the appropriate dose. Several phone calls later, we convinced the patient that what works for cats and dogs would probably be sufficient for him.
If only this patient had presented a few weeks later. Bayer has announced that, effective Oct. 1, praziquantel tablets are available only through limited distribution (http://www.fda.gov/cder/drug/shortages). Health care professionals may obtain the product by contacting Bayer Customer Service (203-812-2000). It is hoped that praziquantel will soon be available for normal distribution.
This is not the only trouble I’ve recently had treating parasitic infections, even in this affluent corner of the United States. Simple consults are turning into 10-hour nightmares, attempting to obtain appropriate therapies for my capitated HMO-based Asian Indian population. It is now believed that ~40% of the software engineers in Silicon Valley are Asian Indians (~70% of whom have positive PPDs—you do the math), all of whom make sufficient salaries to afford annual visits back home and frequent visits from elderly parents. I recently saw an engineering manager who frequently travels between Silicon Valley and Bangladesh, who developed acute left upper extremity swelling, axillary lymphadenitis, and significant peripheral blood eosinophilia (~42%). Thinking he might have contracted lymphatic filariasis, I ordered the appropriate laboratory studies and prescribed a single 12-mg dose of ivermectin (Stromectol).
Again, none of the local pharmacies were able to provide the drug. Stanford Medical Center’s pharmacy promised me over the phone that they would hold onto 12 mg for this patient, but when he arrived to pick up his prescription, they turned him away—he did not have a Stanford prescription. Apparently it wasn’t enough that I was on staff and the patient was willing to pay cash, the patient had to have been seen at their facility. The Santa Clara Valley Medical Center’s (SCVMC) pharmacists were willing to help and secured a supply of the drug for us, but the patient also had to be registered at the county’s facility before the drug could be dispensed. This entailed scheduling him an appointment in SCVMC’s Infectious Disease Clinic, which wasn’t a big deal, except that the county does not accept his HMO insurance and his insurance refused to authorize the visit. Why should the HMO pay to have the patient seen by me in the SCVMC ID Clinic when I had just seen him in the HMO clinic? It was all too confusing for capitated HMO care. Finally, the patient in desperation agreed to pay for his visit to the county clinic, we waived as much of the fee as we could, got him registered in the system, and got him the drug. All for three little tablets of ivermectin.
You have reached your article limit for the month. Subscribe now to access this article plus other member-only content.
- Award-winning Medical Content
- Latest Advances & Development in Medicine
- Unbiased Content