Olfat Saleh Ahmed Mohammed, Abdul Rahman Alawi Bin Yahia and Adel AM Saeed
Abstract
Background: In-use stability refers to products in multi-dose containers that are at risk of losing their contents because of
repetitive opening and closure.
Objectives: To determine the duration that multi-dose paracetamol (PCM) oral suspension may be used after the first dosage
has been removed without affecting the product’s integrity.
Method: Original PCM samples (Panadol®) were chosen and stored in six different storage conditions that represent in-home
storage conditions. The study was designed to simulate as closely as possible a real usage of the multi-dose container products for
in-use stability assessment. Visual inspection and a pH meter were used to track the change in colour and pH values respectively.
The stability was assessed using the UV spectroscopic method. The HPLC method was used to determine the presence of PCM
impurities.
Results: The odor of all samples appeared to be acidic strawberry at the end of the study however, the pH values of all samples
remained within the USP acceptable limit. Samples stored under refrigeration and kept within the outer carton experienced the
least degradation. Calculated T90% was about 5.3 months in the most stable storage condition (condition A) and just (3.45 months)
in the least stable one (condition F). PCM impurity, p-aminophenol (PAP), appeared in amounts exceeding the allowable BP limits
(0.1%) in all samples except condition A.
Conclusion: The maximum in-use shelf life of the original brand PCM suspension was 5.5 months hence the use of PCM after
that should be avoided
د. عادل أحمد محمد سعيد | Dr. Adel Ahmed Mohammed Seaad | 13646