In vitro evaluation of sustained released matrix tablets containing ibuprofen: a model poorly water-soluble drug

ABSTRACT A matrix system was developed that releases ibuprofen (IB) over a 12-hour period and the influence of the polymer type and concentration on the release rate of the drug was evaluated. Tablets containing different concentrations of Carbopol (CP), hydroxypropyl methylcellulose (HPMC), or ethyl cellulose (EC) were prepared using direct compression and the drug content, content uniformity, hardness, friability, dissolution performance, and in vitro release kinetics were examined. Formulated tablets were found to be within acceptable limits for physical and chemical parameters. The release kinetics of the Carbopol(r)971P 8% formulation showed the best linearity (r 2 =0.977) in fitting zero-order kinetics, suggesting the release rate was time independent. The drug release from tablets containing 8% CP was extended over approximately 18 hours and the release kinetics were nearly linear, suggesting that this system has the potential to maintain constant plasma drug concentrations over 12 hours, which could reduce the frequency of administration and the occurrence of adverse effects associated with repeated administration of conventional IB tablets.

An analysis of unused and expired medications in Mexican households.

BACKGROUND: Unsafe storage of unused medications at home leads to an increased risk of toxicity, accidental childhood poisoning or risk for suicide, whereas an improper disposal of unwanted/expired medications from household raises concern about environmental pollution. OBJECTIVE: The aim of the study was to characterize expired medications collected according to the types of therapeutic groups, pharmaceutical dosage forms, expiration dates and were prescribed or over the counter drugs, and whether they came from Mexican health system or purchased by patients themselves. SETTING: The study was conducted in the metropolitan area of Monterrey during a 12-month period from March 2012 to February 2013. METHOD: Unused/expired drugs were collected according to the collection and disposal of expired medication program instituted by the Department of Health of the State of Nuevo León. Pharmacists and students from The Autonomous University of Nuevo León recorded types of therapeutic groups, total of medicines in each group, among other classification criteria. MAIN OUTCOME MEASURE: The proportion of every collected therapeutic group, type of dosage forms, and expiration date. RESULTS: The amount of medications classified was 22,140 items corresponding to a 30 % of the total collected medications in that period of time; most of them belonged to the non-steroidal anti-inflammatory drugs (16.11 %). According to the pharmaceutical dosage forms, results showed that a high percentage were solid dosage forms (73.39 %), of the total unused/expired medications, most of them were prescription drugs (91 %) which were purchased at private pharmacies. Expiration date of medications ranges from 1995 to 2016, being 2011 the outstanding year (36.66 %). CONCLUSION: Addressing the aspect of unused drug disposition constitutes a challenge for Mexican government, due to health implications related to inadequate disposition. No matter how efficient the programs of collection and disposal of expired drugs are, none of them can collect all unused or expired drugs, that is the reason why the best approach might be to prevent this need.