Top 10 Common Medication Errors-Drug #9: Clonidine

Medication errors in the pediatric population occur in both the inpatient and outpatient settings. In fact, pediatric medication errors occur in the latter setting at a rate of about 16% of cases.¹

Many potential medication errors may occur. In this series, I focus on 10 errors that are seen frequently in outpatient clinics. In previous articles, I focused on common errors associated with infant acetaminophen,² insulin,³ ceftriaxone,⁴ hydralazine and hydoxzyine,⁵ amoxicillin/clavulanic acid,⁶ ketorolac,⁷ ciprofloxacin,⁸ and carbamazepine.⁹
Medication Error #9: Clonidine
Clonidine (5 mg [1 mg/kg/dose] PO q8h) was prescribed for a 1-month-old boy (weight, 5 kg) for neonatal abstinence syndrome (NAS). His parents filled this prescription at a local pharmacy. After taking a few doses of the medication, the boy became extremely lethargic. He was seen at the clinic and was found to be hypotensive and was admitted to a nearby hospital.

What is the problem here?

Discussion
Clonidine has been shown to be an effective medication for hypertension and attention-deficit/hyperactive disorder (ADHD), but it also can be used for NAS.¹⁰ The problem in this case is that the dose should have been in micrograms (1 mcg/kg/dose) instead of milligrams.¹¹

The usual dosage of clonidine for various indications can be in either micrograms (like that for NAS) or milligrams (like that for ADHD).¹¹ Clinicians may mistakenly forget the unit for the specific indication for which they are prescribing. It is always good to write down the indication on the prescription as a double-check method.

Clinicians should be cautious when prescribing or compounding the suspension formulation of this medication because thousands-fold errors have taken place when the clinician or the pharmacist mistakenly interpreted the unit as mg/mL instead of mcg/mL.¹² Also, because different concentrations of the compounded suspensions exist, clinicians should write down the concentration of the suspension (10 mcg/mL or 100 mcg/mL) if “mL” is written as the dose. If “mcg/mL” is written as the concentration, clinicians also should write the dose in “micrograms” instead of “milligrams” to avoid the unit-conversion mistake.

This error may have been prevented if either the physician or the pharmacist who filled the prescription realized that clonidine for NAS should be dosed in mcg/kg instead of mg/kg.

References
1. Kaushal R, Goldmann DA, Keohane CA, et al. Adverse drug events in pediatric outpatients. Ambul Pediatr. 2007;7:383-389.
2. So J. Top 10 common medication errors-and how to avoid them: Drug #1: acetaminophen. September 19, 2011.
3. So J. Top 10 common medication errors-and how to avoid them: Drug #2: insulin. October 18, 2012.
4. So J. Top 10 common medication errors-and how to avoid them: Drug #3: ceftriaxone. November 28, 2012.
5. So J. Top 10 common medication errors-and how to avoid them: Drug #4: hydroxyzine and hydralazine. December 28, 2012.
6. So J. Top 10 common medication errors-and how to avoid them: Drug #5: amoxicillin/clavulanic acid. February 1, 2013.
7. So J. Top 10 common medication errors-and how to avoid them: Drug #6: ketorolac. February 27, 2013.
8. So J. Top 10 common medication errors-and how to avoid them: Drug #7: ciprofloxacin. April 2, 2013.
9. So J. Top 10 common medication errors-and how to avoid them: Drug #8: carbamazepine. April 29, 2013.
10. Broome L, So TY. Neonatal abstinence syndrome: the use of clonidine as a treatment option. Neoreviews. 2011;12:e575-e584.
11. Taketomo CK, Hodding JH, Kraus DM. Pediatric Dosage Handbook. 18th ed. Hudson, OH: Lexi-Comp; 2011.
12. Romano MJ, Dinh A. A 1000-fold overdose of clonidine caused by a compounding error in a 5-year-old child with attention-deficit/hyperactivity disorder. Pediatrics. 2001;108:471-472.