Content of Diphenhydramine in Various Over-the-Counter Medications Using Ultraviolet/Visible Spectrometry
Disciplines
Analytical Chemistry | Chemistry
Abstract (300 words maximum)
Diphenhydramine is an antihistaminic medication used to alleviate symptoms such as watery eyes, itching, runny nose, and coughing. Among the various brands of diphenhydramine, Benadryl is the most used. Some brands are labelled as containing 25 mg per tablet, which is the same amount that Benadryl is acclaimed. The question is, in consideration for the consumer, how close to Benadryl are the amounts of diphenhydramine in the various brands? What is the magnitude of the variance? Four sample brands of Walgreen’s brand (waldryl), Walgreen’s liquid (wal-dryl cherry), Benadryl, and Wal-Mart brand (Equate) were prepared and analyzed for their content of diphenhydramine using spectroscopy. Based on the diphenhydramine structure, a Cary 100 UV Spectrometer was our choice for collecting data. A calibration equation was developed using standard solutions to quantify the different brands. Benadryl was found to be 25.03 mg/tablet, boasting a 0.11 percent error. For the liquid cherry-flavored Wal-dryl brand, the strength was determined to be 26.23 mg, with a 4.92 percent error, while the Wal-Mart Equate brand was determined to be 27.52 mg, with a 10.08 percent error. Walgreens was determined to have a dosage/strength of 34.50 mg for their Wal-dryl brand, with a 38.01% error.
Academic department under which the project should be listed
CSM - Chemistry and Biochemistry
Primary Investigator (PI) Name
Huggins Z. Msimanga
Content of Diphenhydramine in Various Over-the-Counter Medications Using Ultraviolet/Visible Spectrometry
Diphenhydramine is an antihistaminic medication used to alleviate symptoms such as watery eyes, itching, runny nose, and coughing. Among the various brands of diphenhydramine, Benadryl is the most used. Some brands are labelled as containing 25 mg per tablet, which is the same amount that Benadryl is acclaimed. The question is, in consideration for the consumer, how close to Benadryl are the amounts of diphenhydramine in the various brands? What is the magnitude of the variance? Four sample brands of Walgreen’s brand (waldryl), Walgreen’s liquid (wal-dryl cherry), Benadryl, and Wal-Mart brand (Equate) were prepared and analyzed for their content of diphenhydramine using spectroscopy. Based on the diphenhydramine structure, a Cary 100 UV Spectrometer was our choice for collecting data. A calibration equation was developed using standard solutions to quantify the different brands. Benadryl was found to be 25.03 mg/tablet, boasting a 0.11 percent error. For the liquid cherry-flavored Wal-dryl brand, the strength was determined to be 26.23 mg, with a 4.92 percent error, while the Wal-Mart Equate brand was determined to be 27.52 mg, with a 10.08 percent error. Walgreens was determined to have a dosage/strength of 34.50 mg for their Wal-dryl brand, with a 38.01% error.