Diarrhea is one of the leading killers of children under five years old in Nigeria. To tackle this challenge, many activities were conducted by government institutions, nongovernmental organizations, and private companies to promote the usage of the best treatment for the disease: the combination of Zinc and Oral Rehydration Salts (ORS). One of the activities, undertaken by the Clinton Health Access Initiative (CHAI), is hiring and training peer detailers to explain the benefits of the treatment to patent and proprietary medicine vendors (PPMVs), a major source of primary healthcare in Nigeria. This paper investigates the effectiveness of this information dissemination program for treatments of children's diarrhea in Nigeria. Two aspects are considered when evaluating the effectiveness of the program: awareness (knowledge) and availability (inventory) of Zinc and ORS among PPMVs. We performed exploratory data analysis and statistical hypothesis tests, and found that the percentage of PPMVs with the desired knowledge of treatments for children's diarrhea increases significantly in most states in Nigeria after the peer detailing. On the other hand, no significant patterns are detected for the percentage of PPMVs with inventory of the treatments. Logistic regression models with confounding factors suggest that PPMVs promoted by CHAI have significantly higher ratios of both the knowledge and inventory of the best treatment for children's diarrhea.