The Institute of Medicine's recent report, Preventing Medication Errors, concluded that at least 1.5 million preventable adverse drug events occur in the United States each year. Ortho-McNeil Neurologics (OMN) Inc and Johnson & Johnson Pharmaceutical Research & Development have become aware of prescribing and dispensing errors involving 2 OMN products: Topamax (topiramate) tablets and the formulations for both Razadyne ER (galantamine HBr) and Razadyne (galantamine HBr). Razadyne was formerly known as Reminyl.

Dispensing confusion between 2 drugs with similar brand names and doses has led to medication errors. For example, a mix-up was reported between Topamax and AstraZeneca's Toprol XL (metoprolol succinate). Topamax Tablets and Topamax Sprinkle Capsules are indicated as initial monotherapy in patients at least 10 years of age with partial-onset or primary generalized tonic-clonic seizures. Furthermore, the medications are indicated for adults for the prophylaxis of migraine headache.

Toprol XL, on the other hand, is used to treat hypertension. It also is used for the long-term treatment of angina pectoris and for stable, symptomatic (New York Heart Association Class II or III) heart failure of ischemic, hypertensive, or cardiomyopathic origin. Possible explanations for medication errors include the similarity of the names of the 2 products, the proximity of the bottles of each medication on pharmacy shelves, and the proximity of the product brand names in computerized listings. In addition, other similarities between the drug products include mnemonic abbreviations in computerized listings incorporating the first 3 letters and the dose (eg, "TOP25") and identical dose strengths, dose titration, and starting doses.

Another example of errors with similarly named medications involved reports of confusion between Takeda Pharmaceuticals Inc's Rozerem (ramelteon) and Razadyne ER and Razadyne. These drug products all are available as 8-mg tablets. Rozerem is indicated for the treatment of insomnia characterized by difficulty with sleep onset. Both formulations of Razadyne are indicated for the treatment of mild-to-moderate dementia of the Alzheimer's type.

Prescribing mistakes with different formulations have been reported and have led to incorrect administration of the medication by patients and their caregivers. The immediate-release Razadyne tablet is to be administered twice daily, and the extended-release Razadyne ER capsule is to be administered once daily. The factors that may have led to medication errors include omission of the formulation on the prescription order and incorrect administration directions from the prescriber.

Whereas potential medication errors have multiple system causes, the role of pharmacists in avoiding such errors is crucial. Increased awareness of prescribing and dispensing errors, combined with additional verification measures, can help keep the wrong medication from reaching patients.

Recommendations for Avoiding Names Confusion

• Place similarly named drug products apart from each other on the pharmacy shelf
• Verify the brand and generic names on written and oral prescriptions
• Counsel patients about the brand name, indication, and correct use of the medication
• Install sound-alike/look-alike namealert warnings about the namepair confusion with Topamax and Toprol XL
• Avoid the use of confusing drug mnemonics such as "TOP25"

Recommendations for Avoiding Formulations Confusion

• Verify the prescriber's intent to write for the correct medication. A prescription reading "Razadyne QD" may be incorrectly written; the prescription needs to be verified. A script reading "Razadyne ER BID" may be incorrectly written; the prescription needs to be verified.
• Counsel patients and their caregivers about the proper way to administer the medication. Patient education on taking medication properly is available at www.razadyneer.com.
• Double-check the bottle for the proper formulation before dispensing
• Install a pop-up alert on the pharmacy computer with wording regarding possible formulation confusion and the need for medication verification.