This research is a self-controlled study. One injected arm of the patient will be assigned to the intervention group and the other arm to the control group. İn the experimental arm, the research nurse working in the Coronary Intensive Care unit (CICU) applied 5-6 drops of HP oil on one arm of the patient with a patting motion 2 hours before the injection. The area was left open for the oil to be absorbed. Only this nurse who administered the injection knows on which arm the oil was applied. The assessment of ecchymosis and pain at the injection site was performed by two other investigators at the 48th hour of the injection (Single blind).

This research is a self-controlled study. One injected arm of the patient will be assigned to the intervention group and the other arm to the control group.In the control arm, no treatment was performed before injection.The assessment of ecchymosis and pain at the injection site was performed by two other investigators at the 48th hour of the injection (Single blind).

The research nurse working in the CICU applied 5-6 drops of hypericum perforatum oil on one arm of the patient with a patting motion 2 hours before the injection. The area was left open for the oil to be absorbed. Only this nurse who administered the injection knows on which arm the oil was applied.

The patient's pain was evaluated with Visual Analogue Scale (VAS) 48 hours after the injection. Visual Analogue Scale is a reliable pain assessment scale to determine the pain felt by patients at the injection site. The VAS is a self-report scale consisting of a horizontal line (10 cm long) with anchor points "no pain" and "worst possible pain". The patient is asked to mark the place on this line that best describes the intensity of pain. A marking of "0" means "no pain". Marking "10" means "'intolerable pain". In this way, the patient scores his/her pain between 1-10.

Ecchymosis was evaluated at 48th hours after injection in the study. A transparent ruler that allows millimetric measurement was used to measure the ecchymosis at the injection site. The discoloration at the injection site was measured in millimeter. Ecchymosis was defined as an area of discolored skin of more than 2 mm appearing 48th hours after administration. The maximum horizontal extent (diameter) of the bruise was recorded regardless of whether the bruise was regular or uneven in shape at the time of measurement. According to previous studies, bruise size was analyzed according to 3 categories: no bruise (0-1 mm), small bruise (2-5 mm) and large bruise (>5 mm). In our study, bruises >2 mm in size was accepted as ecchymosis.