The Misuse of Compounding By Pharmacists
Bruce A. Bouts, RPh, MD, FACP
Compounding is the creation of a drug product by mixing ingredients. For hundreds of years this was the exclusive way pharmacists practiced. However, as professional manufacturing developed, compounding decreased. Fifty years ago, about 60% of medications were compounded. Today, only about 1% of new prescriptions are compounded, but compounding may be undergoing a resurgence.Legitimate Use
State and federal laws permit compounding because it sometimes provides value to patients. In most hospitals, intravenous antibiotic solutions, total parenteral nutrition units, and special pediatric dosages are compounded with products specially manufactured for these purposes. In community pharmacies, concentrations, dosage forms or combinations of medications that are unavailable or not readily available can be manufactured. In a pinch, compounding can be used to prepare products that are hard to acquire or are temporarily unavailable from their manufacturer. Very rarely, products that are free of dyes or preservatives are required. Community pharmacy compounding requires a written prescription specifying that the product be compounded for the specific patient. It is assumed that the formula will be written on the prescription so that other pharmacists can provide refills using the same recipe.Questionable Use
Most compounding is done honestly at physician request. When I practiced pharmacy, most requests came from dermatologists who wanted ointments or creams made to their specifications. However, the profit motive is luring pharmacists to bend the rules in situations where bulk ingredients are available for preparing products that cost less than brand-name drugs. In some cases, savings are passed along to the patients; but in other cases, they are not.Increasingly, the idea to compound a product comes from the pharmacist's request—whether a comparable generic product is available or not. In some instances, existing products are remanufactured to "tailor the product to the patient." This involves, for example, the preparation of 5 mg capsules from the comparatively less expensive 20 mg tablets of Vasotec (an antihypertensive drug). The FDA requires manufacturers to meet stringent quality control measures for the contents of each tablet and to document how quickly the drug dissolves in the stomach. Compounded capsules may vary significantly in dosage and absorption characteristics, with no independent check of quality or variation. Strictly speaking, many compounded products could be viewed as an unapproved new drug items.
In addition, compounding enables pharmacists to create what amounts to their own line of generic nonprescription products. Manufacturers of generic drugs are required to show quality control analyses, while pharmacists are not. Some pharmacists are even promoting compounded products whose ingredients are based on interpretations of preliminary research. This practice lacks the safeguards associated with legitimate experimental trials.
Laser printers enable pharmacists to make professional-looking labels that do not state where a product is manufactured, making it difficult or impossible for the patient or physician to tell whether a product has been compounded. In many cases, the quality, purity, and potency of bulk ingredients cannot be assured. Dr. John Perrin at the University of Florida has noted the powder used to make Caverject (a patented, injectable product used for diagnosing and treating certain types of erectile dysfunction) is imported illegally from Czechoslovakia, enabling the pharmacist to make, in effect, an unapproved generic for a patented product. The pharmacist has no way to determine whether the powder used for such a product has degraded before compounding or is contaminated with bacteria.
I am quite concerned about the safety of compounded products. A segment of the May 12, 1998 "ABC News" dealt with of improper compounding and pharmacy fraud. Done in cooperation with the Florida Board of Health (and Pharmacy), the report checked albuterol (an inhalation agent used for asthma or emphysema) compounded by several pharmacies and noted the lack of regulatory oversight for these products. Samples sent to an independent lab tested superpotent - enough to produce dangerous side effects such as heart rhythm disturbances. The possibility of bacterial contamination was also raised.
Sustained-release products (such as theophylline, a medication commonly used for asthma) are notoriously difficult to manufacture. I do not believe that local pharmacists can produce reliable sustained-release products based on information from third parties. For example, theophylline products now commercially available reliably release their contents into the body over a 12- to 24-hour period. A defective sustained-release agent might instead dump the active agent into the system over a very short period of time (or not at all), leading to palpitations, anxiety, and erratic control of the asthma.
Product stability may also be an issue. Reflavoring antibiotic suspensions "to enhance compliance" does not take into account the stability of the suspension needed to maintain potency. The stability of other ingredients in water or in containers is not even considered when the "house brand" is manufactured. Sterility is yet another issue that most pharmacies are not adequately prepared to deal with. continue to read here
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