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Ndwigah S, Stergachis A, Abuga K, Mugo H, Kibwage I. "Availability and Prices of Antimalarials and Staffing Levels in Health Facilities in Embu County, Kenya." East Cent. Afr. J. Pharm. Sci.. 2019;22(1):26-34. Abstract

Effective treatment of malaria relies on the availability of quality medicines while pricing is a major determinant of affordability. In addition, adequate numbers of competent staff of different cadres is essential for a well-functioning health system and effective health service delivery. The aim of the study was to determine the availability and prices of antimalarial medicines as well as staffing levels in healthcare facilities located in Embu County, Kenya. Antimalarials were sampled from 11 public (government owned) facilities, 29 private pharmacies, 5 private-for-profit and 3 not-for-profit mission health facilities in May-June 2014. The majority of public facilities (91%) had artemether-lumefantrine (AL) tablets in stock. Government and mission facilities did not stock second line antimalarials or sulfonamide-pyrimethamine (SP). All public facilities provided antimalarials free-of-charge to patients. Private pharmacies stocked a wider variety of antimalarials. The facilities studied were stocked with recommended antimalarials both in the private and public domains. No oral artemisinin monotherapies were encountered during the study. Only 45% percent of public facilities employed pharmacists. Of the remaining facilities, 27% employed pharmaceutical technologists while in the rest of the facilities pharmaceuticals were in the custody of nurses. Notably, none of the private-for-profit or mission facilities had pharmacists employed in their establishments; one facility employed a pharmaceutical technologist, while the rest were staffed by nurses. The number of private pharmacies superintended by pharmacists and pharmaceutical technologists were 7 (24%) and 22 (76%), respectively.

Ndwigah S, Stergachis A, Abuga K, Mugo H, Kibwage I. "The quality of anti-malarial medicines in Embu County, Kenya." Malaria Journal. 2018;17:330. Abstract

Background:
Malaria is a major health problem in sub-Saharan Africa where over 90% of the world’s malaria cases occur. Artemisinin-based combination therapy (ACT) is recommended by the World Health Organization as first-line and second-line treatments for uncomplicated falciparum malaria. However, there are a growing number of reports of sub-standard and falsified anti-malarial medicines in sub-Saharan Africa.

Methods:
A cross-sectional study was conducted in Embu County, Kenya on the quality of anti-malarial medicines available in public and private facilities. Sampling of anti-malarial medicines from public and private hospitals, health centers and pharmacies was conducted between May and June 2014. Quality control tests were performed at the Drug Analysis and Research Unit, University of Nairobi, using ultraviolet spectrophotometry and high-performance liquid chromatography. A test for microbial load was also conducted for suspension formulations.

Results:
A total of 39 samples were collected from public and private facilities across the Embu County. A visual inspection of the medicines showed no signs of sub-standard or falsification. All ACT passed identification, assay and dissolution tests. Of 11 suspension samples collected, none failed the microbial load test although one sample had 50 colony forming units (cfu). No oral artemisinin monotherapy medicines were encountered during the survey. Amodiaquine and chloroquine monotherapy products accounted for 5% of the collected samples, despite their ban in Kenya. Two herbal anti-malarial formulations were collected during the survey. Sulfadoxine/pyrimethamine (SP) was also found to be available use for malaria treatment, not in accordance with malaria treatment guidelines.

Conclusion:
All the anti-malarial drugs analysed in this study passed the quality control tests. This is encouraging given the high malaria burden in Kenya. Regulatory actions are required to counter SP and herbal products for malaria treatment.

Ngumo PM, Abuga KO, Njogu PM, Ongarora DSB. "A Stability Indicating Liquid Chromatography Method for the Assay of Rufinamide Bulk Material and Tablets." East Cent. Afr. J. Pharm. Sci.. 2016;19(1-3):16-21. Abstract

A simple, rapid, isocratic stability indicating reverse phase liquid chromatography method was developed for the assay of rufinamide bulk drug and tablets. The method achieved adequate resolution of rufinamide, related substances A and B as well as laboratory generated degradation products. The method uses a Phenomenex® Hyperclone BDS C-18 column (250 × 4.6 mm, 5 μ) maintained at 35 °C and a mobile phase composed of methanol-0.1 M octane sulfonic acid-0.1 M KH2PO4, pH 6.5-water (30:10:5:55, % v/v/v/v) delivered at a flow rate of 1.0 ml/min. The eluents were monitored by means of ultraviolet detection at 210 nm. During validation, the method satisfied the International Conference on Harmonization acceptance criteria for linearity sensitivity, precision, accuracy, and robustness. The developed method may be applied in the routine analysis of rufinamide bulk material and tablets as well as stability studies.

Njaria PM, Abuga KO, Kamau FK, Chepkwony HK. "A versatile hplc method for the simultaneous determination of bromhexine, guaifenesin, ambroxol, salbutamol/terbutaline, pseudoephedrine, triprolidine, and chlorpheniramine maleate in cough–cold syrups." Chromatographia . 2016;79(21):1507-1514. Abstract

A simple, rapid, isocratic, and versatile liquid chromatographic method was developed for the simultaneous
determination of bromhexine, guaifenesin, ambroxol, salbutamol/terbutaline, pseudoephedrine, triprolidine, and
chlorpheniramine maleate in cough–cold syrups commonly marketed in Kenya. Separation was achieved using
a Gemini® NX C18 column (250 × 4.6 mm, 5 μm) maintained at 40 °C and a mobile phase consisting of acetonitrile-0.25 M sodium hexanesulphonate-0.2 M ammonium acetate, and pH 3.0-water (35:4:10:51, % v/v/v/v) delivered at 1.0 mL min−1. The eluents were monitored by means of UV detection at 254 nm. During validation, the method satisfied the International Committee on Harmonization acceptance criteria for linearity, sensitivity, precision, accuracy, and robustness. The developed liquid chromatographic method was applied in the analysis of nine commercial samples obtained from Nairobi City County, Kenya. Extraction procedures were not applied during the assay of the samples, thus significantly shortening the analysis time.

Njuguna NM, Abuga KO, Kamau FN, Thoithi GN. "A liquid chromatography method for simultaneous determination of diphenhydramine, promethazine, chlorpheniramine and ephedrine in cold-cough syrups." Pharmaceutical Chemistry Journal. 2017;51(2):153-158. Abstract

A simple, rapid isocratic liquid chromatography method was developed for the simultaneous determination of diphenhydramine, promethazine, chlorpheniramine, and ephedrine in cold-cough syrups commonly available in the Kenyan market. The influence of the percentage of organic modifier, ion pairing agent, buffer concentration as well as pH and column temperature on the selectivity with respect to analytes was investigated. Optimum chromatographic separation was achieved using a C18 Gemini NX column (250 mm × 4.6 mm, 5 μm) maintained at 40°C and a mobile phase comprising methanol –triethylamine-0.2 M ammonium acetate pH 5.0 -water mixture (50:0.15: 40:9.85, v/v) delivered at a flow rate of 1.0 mL/min. Upon validation, the proposed liquid chromatography method satisfied the International Committee on Harmonization acceptance criteria for linearity, sensitivity, precision, and robustness. The method was applied in the analysis of commercial samples obtained from Nairobi County, Kenya. The method can be used in routine analysis of cold-cough syrups containing the specified compounds.

Keywords: diphenhydramine; promethazine; chlorpheniramine; ephedrine, cold-cough syrups.

Nyamweya NN, Abuga KO. "A Survey of Alcohol-Based Hand Sanitizers in Nairobi: Packaging, Labelling and Regulatory Compliance." East Cent. Afr. J. Pharm. Sci. 23 (2020). 2020;23(2):72-76. Abstract

Alcohol based hand sanitizers are currently recommended for routine use in curbing the spread of the COVID-19 global pandemic. The present survey examined hand sanitizers marketed in Nairobi County with regards to product appearance, packaging, labelling and declared composition. Seventy-six samples were collected from five sites within the Nairobi metropolis - Central Business District, Kibera, Kilimani/Karen, Ngong and Thika. A wide range of non-conformities were observed for the criteria applied. Many samples had incomplete or missing label information, ingredient lists, cautionary warnings, Kenya Bureau of Standards (KEBS) standardization marks and permit numbers. Glycerin, fragrances and carbomers were the most common added ingredients. Poor formulation indicators such as haziness and phase separation were encountered in some products. The median price of the products was KES 250 (USD 2.36) per 100 ml although there was considerable variation in pricing of samples. None of the samples evaluated fully met all the standards for the parameters evaluated. Strict adherence to regulatory standards by producers of hand sanitizers is required to ensure that only compliant products are available on the market.

Nyamweya NN, Lumb PN, Mujyarugamba JC, Abuga KO. "Inactive Ingredients used in Alcohol-Based Hand Sanitizers marketed in the Nairobi Metropolitan Area." PJK. 2021;25(1):17-20. Abstract

Background: Alcohol-based hand sanitizers (ABHS) have become widely used products since the advent of the SARS-CoV-2 coronavirus based COVID-19 pandemic. In addition to ethanol or isopropanol (the active ingredients of ABHS) and water, these products are formulated with a number of ingredients to optimize delivery, efficacy and safety as well as to provide consumer appeal. Despite the widespread use of ABHS, there is very limited information in the literature on the non-alcohol ingredients used in these products.
Objectives: The aim of this work was to determine the inactive ingredients used in ABHS marketed in metropolitan Nairobi.
Methodology: ABHS products were randomly obtained from several locations at retail outlets within the Nairobi metropolitan region. The ingredients used in each ABHS were obtained from the product labels.
Results: The most common inactive ingredients based on percentage frequency of listing on product labels were glycerin (50%), fragrances (36%), carbomer (26%), triethanolamine (18%) and propylene glycol (17%). It was observed that some products incorporated additional antimicrobial agents and preservatives in the formulation. The fragrances and some of the preservatives used in the ABHS products are potential allergens. Incomplete or inadequate ingredient naming was noted for several products.
Conclusions: There is a need for ABHS manufacturers to fully disclose all raw materials used in ABHS products using standardized ingredient nomenclature. ABHS users need to be aware of potential allergens present in respective marketed products.

Nyamweya NN, Kimani SN, Abuga KO. "Chewable Antacid Tablets: Are Disintegration Tests Relevant?" AAPS PharmSciTech . 2020;21:139. Abstract

A recently published FDA guidance on chewable tablets has addressed the quality attributes of this class of dosage forms. This study evaluated disintegration as a quality attribute for a number of commercially available chewable antacid tablets. Additionally, acid-neutralizing-capacity values were evaluated. A number of the products exhibited prolonged disintegration times—which were far longer than those of conventional immediate-release tablets. The mean disintegration times ranged from 6 to more than 60 min in distilled water and from 9 to over 60 min in 0.1 N HCl. The products with longer disintegration times had higher breaking force and tensile strength values. Despite the range in disintegration times, all products met the criteria for acid-neutralizing capacity. These results indicate a need for patients to be aware of the need to thoroughly chew antacid tablets upon administration. Given these considerations, disintegration testing would be a useful quality control test in evaluating these dosage forms as the implicit assumption by the manufacturer that patients will chew the product sufficiently may not be met in every case.

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