BACKGROUND: Antibiotics are over-prescribed for lower respiratory tract infections (LRTI) in nursing home residents due to diagnostic uncertainty. Inappropriate antibiotic use is undesirable both on patient level, considering their exposure to side effects and drug interactions, and on societal level, given the development of antibiotic resistance. C-reactive protein (CRP) point-of-care testing (POCT) may be a promising diagnostic tool to reduce antibiotic prescribing for LRTI in nursing homes. The UPCARE study will evaluate whether the use of CRP POCT for suspected LRTI is (cost-) effective in reducing antibiotic prescribing in the nursing home setting. METHODS/DESIGN: A cluster randomized controlled trial will be conducted in eleven nursing homes in the Netherlands, with the nursing home as the unit of randomization. Residents with suspected LRTI who reside at a psychogeriatric, somatic, or geriatric rehabilitation ward are eligible for study participation. Nursing homes in the intervention group will provide care as usual with the possibility to use CRP POCT, and the control group will provide care as usual without CRP POCT for residents with (suspected) LRTI. Data will be collected from September 2018 for approximately 1.5 year, using case report forms that are integrated in the electronic patient record system. The primary study outcome is antibiotic prescribing for suspected LRTI at index consultation (yes/no). DISCUSSION: This is the first randomised trial to evaluate the effect of nursing home access to and training in the use of CRP POCT on antibiotic prescribing for LRTI, yielding high-level evidence and contributing to antibiotic stewardship in the nursing home setting. The relatively broad inclusion criteria and the pragmatic study design add to the applicability and generalizability of the study results. TRIAL REGISTRATION: Netherlands Trial Register, Trial NL5054. Registered 29 August 2018.