Assessing the stability of lamotrigine dispersible/chewable tablets when stored in blister punch cards.

OBJECTIVES: To determine the stability of lamotrigine dispersible/chewable tablets (DCTs) when stored in blister punch cards (BPCs).

METHODS: Lamotrigine 100 mg DCTs were randomly repackaged into a US Pharmacopeia Class A 1 week cold-sealed BPC. Chemical and physical stability were evaluated over a 60 day period, in controlled conditions corresponding to Climatic Zones I/II (25 °C ± 2 °C; 60% ± 5% relative humidity). At scheduled times, various tests were performed on tablets in their primary packaging (reference samples) and on tablets repackaged (BPC samples). A validated high-performance liquid chromatography method adapted from the US Pharmacopeia was used to quantify lamotrigine.

RESULTS: Lamotrigine content remained within the US Pharmacopeia acceptance range of 90%-110% during the 60 day study period and there were no significant changes compared with reference samples (p = .386). The increase of weight and the reduction of hardness of the repackaged tablets did not affect their dissolution profiles, and no change in appearance was observed. All tests complied with the compendial requirements of the pharmaceutical physical tests.

CONCLUSIONS: Although changes in hardness after 14 days have not impacted on outcomes in terms of compliance with compendial requirements, a cautious recommendation would probably be a BPC storage of lamotrigine DCT of up to 14 days after repackaging.