In a just world, homeopathic medicine would be taken off the shelves because it's just water—not water mysteriously holding the shape of a target antigen, just plain fucking water—yet it has a label aggressively suggesting real-life medical benefits. Homeopathy is the branch of alternative-medicine that the alternative-medicine establishment won't even defend, which is kind of like saying the strip mine the governor of West Virginia won't even defend or the oil rig BP won't even defend or the short sale Lehman Brothers won't even defend. You get the idea.
The principle of homeopathy, or the would-be principle, is that you can dilute a quantity of antigens in a water solution all the way down such that no actual antigen exists in the solution, yet the water will "hold" the shape (or essence or whatever) of the antigen and by extended micro-exposures to the antigen through its fictitious water proxy, a patient will develop some immunity/resistance to the antigen, which might be an allergen like pollen or other things that cause inflammation and thus illness in the body, by consuming the homeopathic shape-solution. This is not how chemistry or physics work, and in addition to a disclaimer from the US National Center for Complementary and Alternative Medicine ("There is little evidence to support ..."), homeopathy has also been dissed very publicly by the British House of Commons.
One US homeopathic supplier has been selling something a bit different, however: penicillin. According to the Register: "Terra-Medica is voluntarily recalling 56 lots of homeopathic drug products in liquid, tablet, capsule, ointment, and suppository forms after it was discovered the alternative treatments potentially contained penicillin or derivatives of penicillin." According to Wired, the bonus antibiotic might be the result of some bonus fermentation during the manufacturing process of the homeopathic supplements, which are marketed under a variety of names and in a variety of forms (suppositories, say).
The recall should be considered quite urgent, as penicillin is a disaster for those allergic to it, a crowd of people that ironically enough might lean toward homeopathy and alt-medicine for the simple reason of having that allergy. One might expect then a larger share of the penicillin-allergic among homeopathy fans/customers. In a statement, the company says, "To date, Terra-Medica has not received any reports of adverse events related to this recall, nor any reports of product tests indicating penicillin content in the products."
This isn't the first time something very real and very potent has been found in homeopathic products (or alt-medicine products generally). Homeopaths have been known to use solutions of arsenic and poison ivy, occasionally allowing quite real-life potent concentrations to make it to market, rather than the 0 percent concentration advertised. Yes, people die. Many more experience non-lethal adverse effects. Death, however, is hard to chart, as it typically comes as the result of denying conventional real-life treatments. One famous case involves a homeopathic researcher that died mid-trial because she'd been self-treating her cancer with homeopathy rather than conventional medicine. Death by delusion, often actively cultivated by the alternative-medicine industry, which is as much an industry as Big Pharma, only it rarely has to answer for its bad claims and real harm.
If you want to see the seeds of "real harm," the conclusion from professional takedowner (of Big Pharma, bad science, fake medicine) and actual doctor Ben Goldacre's crucial read, "What's Wrong with Homeopathy?" is chilling:
Many homeopaths also claim they can transmit homeopathic remedies over the internet, in CDs, down the telephone, through a computer, or in a piece of music. Peter Chappell, whose work will feature at a conference organised by the Society of Homeopaths next month, makes dramatic claims about his ability to solve the Aids epidemic using his own homeopathic pills called "PC Aids", and his specially encoded music. "Right now," he says, "Aids in Africa could be significantly ameliorated by a simple tune played on the radio."
A distressing piece of the Affordable Care Act (Obamacare, OK) that doesn't get much mention is its stance on homeopathy and alt-medicine fake-cures in general. While the House of Commons slams homeopathy across the Atlantic, the US has endorsed it full-on, mandating that insurers treat alt-medicine practitioners the same as conventional doctors, so long as they're state-licensed. What that means is that, in the eyes of Obamacare, someone peddling blessed mystery water and a radiologist or oncologist might as well be rocking the same affirming evidence.
If that doesn't seem rather fucked, you really must read Goldacre's essay linked above. It makes the case as concisely as anything I've read, a primer on placebos, loose evidence, and the art of simply making stuff up to move sketchy pills.