Potential savings from splitting newer antidepressant medications

The newer antidepressants are among the most commonly prescribed classes of medications. A favourable adverse effect profile and approvals for a wider range of disorders than their predecessors have fostered the growth of these drugs. However, newer antidepressants are appreciably more expensive than older medications, and the annual prescription costs of newer drugs are expected to continue to rise at double-digit rates. The price structuring of these medications is largely independent of their pill strengths, and splitting higher strength pills may reduce the average cost per dose by nearly half. Therefore, various health organisations and consumers have been using pill splitting to reduce prescription costs. Antidepressants are well suited for pill splitting because their therapeutic effects depend upon long-term alterations in neurotransmitters, and small variations in dose are not critical.

To examine the potential savings for various purchasers - health organisations and consumers - that can be derived from pill splitting of newer antidepressants.

Product review and simulation study in the US healthcare setting.

All new antidepressants with pill strengths that could be halved and were not in capsular or time-release forms were included. Expenditures for purchasers of these pills were calculated using a variety of factors, such as the level of discounting of official average wholesale costs, average retail costs and the site of prescription dispensing.

Seven antidepressants were included. In 2000, 42% of the pills of these antidepressants were at strengths that permitted splitting. If all eligible prescriptions had utilised split doses, purchasers could have saved over dollars US1.7 billion. The bulk of the saving (dollars US1.5 billion) would have been realised by pill splitting of only three medications - sertraline, paroxetine and citalopram.

The economic rationale for pill splitting of antidepressants is compelling for both health organisations and individual consumers. The literature indicates that when pill-splitters are used or a pharmacy cuts the pills, patients are satisfied and compliance is not reduced. However, pill splitting may be inadvisable for some subgroups of patients with reduced cognition or sensory or motor impairment, or older persons on polypharmacy. Pill splitting can be facilitated by mandating manufacturers to score all tablets, requiring pharmacists to fill prescriptions for split doses, and giving pharmacists incentives for splitting pills for patients. Finally, large-scale studies should be undertaken to examine the clinical effectiveness of, and financial savings from, pill splitting.