Whether working in a hospital, specialty, or retail pharmacy, pharmacists will tell you special considerations are needed when dealing with children and infants. Pharmacists must contend with challenges like weight-based dosing calculations, metabolic differences, adverse reactions, and the use of off-label medications and compounds. Combine those concerns with the fact that many patients are too young to communicate about how medications are affecting them, and you have a recipe for potential errors.
A study on pediatric medication safety in emergency departments, published in Pediatrics in March, notes the ED presents a high risk for medication errors including problems caused by a lack of standardized pediatric drug dosing and formulations, lack of clinical pharmacists, and weight-based dosing. For patients outside the hospital setting, medication errors can happen because of confusing product packaging or use of the wrong dosing tools.
“It’s definitely a challenge,” says Anita Siu, PharmD, BCPPS, of weight-based dosing issues. She is a clinical associate professor at the Ernest Mario School of Pharmacy, Rutgers University, and a clinical neonatal/pediatric pharmacotherapy specialist at Jersey Shore University Medical Center. “You’re not going to treat a neonate within the first days of life the same way as we treat an infant or give the same doses as a child. Whether it’s younger children or older children, there is a lot of weight variation,” she says.
Drugs can be metabolized at different rates between pediatric and adult populations and within pediatric age ranges. Younger children, who weigh less, may metabolize certain medications faster so they might need a dose three times a day rather than twice as for adults. Body water volume impacts medication distribution and pharmacodynamics affects it, too. “Young kids are basically bags or buckets of water,” says Siu. “Because they have a larger volume of distribution, based on weight, we may need to give them more medicine.”
This is often the case with neonates. For example, they may need more gentamicin than older patients, says Susan Warrington, PharmD, BCPPS, clinical pharmacy specialist at the Lehigh Valley Health Network in Allentown, PA.
Capturing and documenting patient weight accurately and converting pounds to kilograms is crucial because dosages are based on kilograms. If a parent says a child weighs 22 pounds but the weight is recorded as 22 kg, the child could get 2.2 times the dose he or she should be getting, Siu says. The Joint Commission recommends all pediatric hospital patients be weighed in kilograms at admission and within four hours of an emergency situation.
Siu asserts that clinicians should always write the weight on prescriptions and pharmacists should double check the calculations.
Warrington, who does clinical rounds as part of the hospital’s medical team, says she and her colleague, Kristin Held Wheatley, PharmD, BCOP, are able to assess how patients are handling medications and make modifications. Warrington says they also look at polypharmacy issues to “make sure every medication on the list is truly needed” and avoid therapeutic duplication.
Wheatley, a clinical pharmacy specialist in pediatric oncology and infectious diseases, says she often asks if a patient needs to receive a medication by IV or recommends an IV if an oral medicine nauseates the patient.
Another challenge is dealing with off-label medications that haven’t been studied for effectiveness in children. A 2014 statement from the American Academy of Pediatrics (AAP) noted that use of off-label drugs “remains an important public health issue, especially for infants, young children, and children with rare diseases.” AAP noted pediatric labeling information exists in less than 50% of products.