Background: One of the non-pharmacological methods used to reduce behavioural problems of Alzheimer's patients and the negative emotions accordingly experienced by caregivers consists of interventions performed according to the Progressively Lowered Stress Threshold (PLST) model. Methods: This randomized controlled study aimed to determine the effect of interventions performed according to PLST on the care burden, care satisfaction, and life satisfaction of caregivers of middle and advanced stage Alzheimer's disease patients, and on the neuropsychiatric symptoms and agitation levels of these patients. The research was conducted with a total of 29 caregivers divided into intervention (15) and control ( 14) groups. Data were collected using an Introductory Information Form, plus the Standardised Mini-Mental State Examination, Neuropsychiatric Inventory, Cohen-Mansfield Agitation Inventory, Carer's Assessment of Satisfaction Index, and Life Satisfaction Scale. Three home visits were made to the caregivers by the researchers in the first, second, and twelfth weeks of the intervention. During the home visits, face-to-face training was given as necessary to the individual caring for problems identified in the nursing care plan according to PLST. Results: As a result of the PLST training, there was a decrease in the behavioural problems of Alzheimer's patients, along with a decrease in the care burden of the caregivers and an increase in their care satisfaction. When the scale total scores of the individuals in the intervention and control groups were compared, it was found that only caregivers' care satisfaction increased at a statistically significant level (P < 0.05). Conclusion: At the end of the training given according to PLST, it was found that behavioural problems of Alzheimer's patients and the care burden of caregivers had decreased, and the care satisfaction of caregivers increased. It is recommended that Alzheimer's patients and their caregivers be given training and interventions according to PLST.