Stability of reconstituted amoxicillin clavulanate potassium under simulated in-home storage conditions

Oral suspensions of antibiotics are mainly available as dry powders for reconstitution. Many reconstituted antibiotic suspension is to be kept refrigerated in order to get the optimal benefit from the drug. However, many patients do not keep to the specified storage conditions for different reasons like no refrigerator and irregular power supply that may result in various degrees of degradation of the product. Pharmacists are therefore challenged on how to counsel patients when there is no refrigeration or erratic power supply for refrigeration. This study investigated stability of amoxicillin-clavulanate potassium suspension in simulated in-home conditions of erratic power supply and no refrigeration. Amoxicilin clavulanate suspensions were reconstituted and stored in three different in-home storage conditions with temperature ranging between 5-29oC over a period of 10 days. Samples from the suspension were assayed using a validated HPLC method. Percentage concentrations of amoxicillin-clavulanate potassium were over 90% up to fifth day, degradation was extensive by seventh day with amoxicillin concentration falling below 80% in two conditions while clavulanate had values less than 70% in all the three conditions. Reconstituted amoxicillin clavunate potassium stored at room temperature (27-29oC) is stable for five days, use of reconstituted suspension that was not properly refrigerated after the fifth day should be discouraged.