Amlodipine besylate-excipients interaction in solid dosage form.

Area of Science:

• Pharmaceutical Sciences
• Drug Formulation
• Chemical Stability

Background:

• Amlodipine besylate is a widely used antihypertensive medication.
• Understanding drug-excipient compatibility is essential for stable solid dosage forms.
• Previous studies have highlighted potential interactions with common pharmaceutical ingredients.

Purpose of the Study:

• To evaluate the compatibility of amlodipine besylate with various pharmaceutical excipients in solid formulations.
• To identify factors influencing amlodipine besylate stability.
• To recommend optimal formulation strategies based on stability data.

Main Methods:

• High-performance liquid chromatography (HPLC) was employed to assess amlodipine besylate stability.
• Binary (1:1) and multicomponent mixtures with excipients were subjected to stress conditions (65°C and 40°C/75% RH).
• HPLC coupled with mass spectrometry (HPLC-MS) was used to identify degradation products.

Main Results:

• Amlodipine besylate demonstrated stability in binary mixtures with most excipients under tested conditions.
• Mixtures containing lactose, magnesium stearate, and water induced significant instability.
• Amlodipine besylate glycosyl was identified as the major degradation product, consistent with the Maillard reaction.

Conclusions:

• Lactose is a key excipient that can compromise amlodipine besylate stability due to the Maillard reaction.
• Magnesium stearate and water also contribute to amlodipine besylate degradation.
• Lactose-free amlodipine besylate formulations are recommended to ensure safety, quality, efficacy, and process efficiency.