Pharmaco-Economic Analysis of Brands of Antacid Formulations Available in Ishaka Town Using Titrimetric Method

ABSTRACT Pharmaco-economics involves comparing the cost and consequences of products and services and Cost-effectiveness is the relationship between cost and effectiveness of a given drug. ANC of an antacid is one of the ways of evaluating effectiveness of antacid brands. ANC (mEq per unit dose) is the ability of the antacid to neutralize gastric acid (Shery et al., 2013), and it should be greater or equal to 5mEq per unit dose(FDA), where a unit dose of 0.5g for tablets and 5ml for suspensions was used. Cost was evaluated using cost per unit dose. Antacid formulations (tablets/suspensions) act by neutralizing gastric acid which is mainly hydrochloric acid (]-!Cl). Normal concentration of stomach HCl is about 0.082M and a person experiences stomach acid when HCl concentration increases to about 0.1 M. Antacids are indicated for peptic ulcer disease (PUD), gastro esophageal reflux disease (GERD), acid indigestion and bloating. Antacids contain one of the following compounds as their active ingredients: Magnesium hydroxide, calcium carbonate, sodium bicarbonate, aluminum hydroxide, magnesium trisilicate or ammonium citrate. Side effects due antacid use include: milk-alkali syndrome, osteomalacia, hypophosphatemia, constipation, diarrhea, aluminum-intoxication and dose dependent rebound hyperacidity (Omotosobayomi et al., 2015). The study design was experimental and during this study, sixteen marketed brands of vanous dosage forms were purchased from pharmacies in lshaka and their details recorded. 0.5g of tablet powder or 5ml of suspension was weighed into a 250ml flask. A known volume of O. l M l !Cl (20ml for tablets and 30ml for suspensions) was added to the flask and mixture swirled, then boiled for 15 seconds and cooled to room temperature. 8 drops of bromothymol blue were added and the mixture turned yellow. If it was not yellow, more HCI could be added until it turned yellow. The volume of excess acid added was recorded. The mixture was then titrated against 0.1 M NaOH until a blue end point was reached. The data was entered into Microsoft Excel and analyzed using ST AT A version 12 in which the ANOVA was used to test for differences amongst the ANC values and the costs per unit dose of the selected antacids. A 5% level of significance was considered and a p value less than that was taken to be significant. In this study, the ANC values and costs per unit dose of different brands were significant (p