TRT is poorly characterized, particularly among older men with multiple comorbidities. Notably, a large randomized trial of TRT among men older community-dwelling men was prematurely discontinued because of a significantly increased risk of cardiovascular events in the treatment group relative to placebo and a recent study of a male Veterans cohort associated TRT use with increased mortality, myocardial infarction and stroke. Regardless, several new Diatrizoic acid testosterone replacement products have been introduced and prescriptions for novel formulations such as topical preparations have also increased rapidly. Numerous regions have attempted to curb testosterone utilization. In Ontario, where older individuals receive universal drug coverage through the provincially funded Ontario Drug Benefits program, no restrictions were in place governing the use of these drugs prior to the listing of topical TRT in 2005. However, to limit TRT prescribing, in 2006 the provincial government restricted coverage of all formulations of TRT to the treatment of new endocrinopathy occurring at any level of the hypothalamic-pituitary-testicular axis, defined as a “confirmed low morning serum testosterone levels associated with symptomatic testicular disease”. Despite many changes to the availability and diversity of TRT options over the past decade, population-based studies examining the impact of these changes on prescribing trends of these drugs among older men are lacking. We investigated temporal trends in rates of testosterone use among elderly men and the impact of the introduction of prescribing restrictions on the use of these products in Ontario. Finally, we sought to identify the characteristics of men who commenced treatment with TRT to appreciate the presence of comorbidities that could potentially impact the safety of testosterone in this population. In the primary analysis, we conducted time series analysis using autoregressive integrated moving-average models to examine the impact of the restriction of public drug coverage of testosterone products in March 2006 on the quarterly prevalence of testosterone therapy. We stratified all analyses by testosterone formulation. Seasonality was assessed and taken into account when developing the ARIMA models. We used the correlograms depicting autocorrelation, partial autocorrelation, and inverse autocorrelation functions to guide initial model selection. We assessed autocorrelation at various lags using the Ljung-Box Chi-square statistic and stationarity using the augmented Dickey-Fuller test. The change in reimbursement status in Q1 2006 was reflected as a step function in the regression model. In this study spanning 15 years, we demonstrated a substantial increase in the use of TRT over time, despite the lack of long-term efficacy and safety data in elderly men. Acknowledging this uncertainty and restricting the criteria for TRT reimbursement on the public drug formulary led to a sharp decline in use; however this decline was temporary as TRT Homatropine Bromide utilization resumed its upward trend following the introduction of topical TRT. By 2010, the rate of testosterone use exceeded the earlier peak rate and continued to rise thereafter. By the first quarter of 2012, one in every 90 men aged 66 and older were being treated with testosterone. This finding indicates that this policy, although designed to restrict inappropriate prescribing of TRT, was only briefly effective by initially lowering rates of injectable and oral testosterone use, and relatively ineffective in curtailing growth of topical testosterone products.