Neurologic oral manifestations caused by a new formulation of mirtazapine

A conventional tablet of mirtazapine was introduced for treatment of depression in the mid-1990s. In February 2003, a new formulation of mirtazapine, the orally disintegrating tablet Remeron-S, was introduced in Sweden. The rationale is that patients experiencing difficulties in swallowing could let this new formulation melt before swallowing.1 In Sweden, health care professionals with permission to prescribe drugs, should report suspected adverse drug reactions (ADRs) to the regulatory authority, the Medical Product Agency, and the data are transferred online to the Swedish database (SWEDIS) for ADRs. The main aim of spontaneous reporting systems, such as the one in Sweden, is to produce signals regarding new potential ADRs. We examined all ADR reports in the SWEDIS database related to the conventional mirtazapine (Remeron), as well as those related to the orally disintegrating tablet (Remeron-S) that had been transferred to the database from January 1996 to September 2004. Furthermore, we compared these with other substances that had high total numbers of reports of paresthesia, and related to drug consumption measured as the number of defined daily doses (DDD). In brief, “DDD is the assumed average maintenance dose per day for a drug used for its main …