Background <p>Elderly individuals with chronic diseases often depend on family caregivers for medication management, a responsibility that can contribute to caregiver stress and psychological burden. This study investigated the effect of a supportive educational intervention focused on medication management on the perceived stress of family caregivers.</p> Methods <p>A randomized parallel-group trial was conducted in 2025 with 52 caregivers of elderly patients living in Gonabad and Ferdows counties. Participants were randomly assigned to intervention and control groups. Caregivers in the intervention group attended three face-to-face home training sessions (30–60&#xa0;min each, held weekly), supplemented with two to three follow-up telephone calls. Training covered reviewing medication bags, correct administration methods, timing, side effects, preparation, storage, and supply of medications. The control group received no intervention. Data were collected using a demographic questionnaire and Cohen’s Perceived Stress Scale before and eight weeks after the intervention. Analyses were performed using descriptive and inferential statistics with SPSS 23.</p> Results <p>The elderly receiving care had a mean age of 78.84 ± 8.79 years. Most had three comorbidities (48.1%) and took five medications concurrently (30.8%). Caregivers had a mean age of 49.76 ± 11.96 years, and most were female (57.7%). Repeated-measures ANOVA showed a significant reduction in perceived stress over time, while the difference between the intervention and control groups did not reach statistical significance (<i>p</i> &gt; 0.05).</p> Conclusion <p>A supportive educational intervention based on medication management can reduce the perceived stress of the elderly’s family caregivers. Applying this approach to the health system can improve the quality of care provision for the elderly and the caregivers’ mental health.</p>