Friday, December 7, 2007

Infant Cough and Cold Product Recall

If you're not feeling the pain of the finals week crunch right about now, it's because you're not a student. Lucky you!

The whole infant cough and cold drug recall isn't really new news; it's been going on for a few months now. And the lawsuit filed by Dimitria Alvarez of Illinois is still pending, as far as I'm aware.

For those unaware of the essential background, many retailers and manufacturers voluntarily recalled many drug combination products marketed for the treatment of cough and cold symptoms in children under 2. The move has generally been well-received by physicians; Pharma has responded to allegations regarding product safety that all of the products on the market have been deemed to be safe when used as directed.

Part of the issue is that there have been very few studies regarding the use of products like dextromethorphan and pseudoephedrine in children, and the new replacement for PSE, phenylephrine, doesn't even have established weight-based dosing guidelines. Many dosages, therefore, are extrapolated from adult doses using various rules of thumb. Clark's rule, for example, suggests dividing the child's body surface area in meters squared by 1.73 (the average BSA for an adult) and multiplying that ratio times the adult dose to get an approximate children's dose. Fried's rule suggests multiplying a child's age in months by the adult dose and dividing the result by 150 when dosing medication for children from 1 to 2 years of age.

These approximations are no substitute for thorough clinical trials. They assume, quite incorrectly, that children are like little adults, and that weight-based dosing is sufficient to guarantee safety. Not only do children have less "body space" in which to distribute a drug dose, increasing its concentration in the blood, but their bodies are less capable of metabolizing and eliminating a given dose. Drug half-life, or time required to eliminate half of the amount of drug in the bloodstream, is typically much greater in children than adults, and not always proportionally so. The half-life of caffeine in healthy adults is 3-4 hours; in newborns, it may be as long as 30 hours. Furthermore, children often respond differently to medications than adults. Antihistamines often produce paradoxical excitement in children whereas they have a sedating effect on older people.

Since many cough and cold products are untested in infants and young children and their efficacy cannot be guaranteed, treating them for cold symptoms is less about treating the child and more about assuaging the concerns of parents. This is particularly true in the case of infants who cannot communicate except by crying; nervous parents will frequently assume that crying is a sign that an infant is uncomfortable and likewise assume that a lack of crying indicates comfort or relief of symptoms. Anecdotally, a pharmacist I work with told me once about a one-year-old who had been prescribed Donnatal elixir. Donnatal is a drug normally used in adults to provide relief of gastrointestinal upset; it contains atropine and other belladonna-derived alkaloids, which slow the movement of the stomach and bowels, as well as phenobarbital, a central nervous system depressant. Donnatal elixir is also about 23% alcohol by volume--it's more alcoholic than many liqueurs, including irish cream! I'm willing to bet that any "therapeutic value" that medication had for a one-year-old primarily manifested itself as "shutting junior up."

I've discussed the popularity of the placebo effect before; since nothing tugs at mom's heartstrings like a crying baby, treatment of illnesses in infants that are not life-threatening is more a matter of making mom feel like she's doing something to help her poor child. As a result, tired physicians or busy pharmacists might be inclined to recommend something just to keep mom happy. From an evidence perspective, pulling these products off the shelves was an excellent move; appropriate non-pharmacologic treatments are frequently available and generally safer. Saline nasal spray is probably a better treatment for nasal congestion in young children overall, and it has the added benefit of soothing dry membranes. The risk versus benefit analysis of cough and cold products, especially in infants, really suggests that they aren't worth using.

If you ask me, the lack of clinical trials in infants and children to support the use of cough and cold products aside from fever-reducing agents (such as acetaminophen and ibuprofen) really nails the issue. It's true that many of the products were used for years before the recall, but the benefits have generally been small--medicating children is frequently done just to make the parents feel better. As such, the recall of these products is no great loss.

If your kid has a cold, think things through; if he's only been sick for a day or two, he's probably going to get better on his own. Nothing you can do is going to make the illness go away faster. Do you really need to do anything but provide the kid with adequate fluids and let things run their course? Is it really worth struggling against the inevitable fact that your child is going to be sick for a few days? I'm hoping that in time parents won't be lamenting the disappearance of these products. They'll adapt to the idea that there are no miracle cures for sale on pharmacy shelves.

No comments: