Pregnancy is considered as one of the most important events in every woman's life, which is not a pleasant event for all women, and in cases where the stages are not managed properly, it can cause a lot of stress on the mother and her family. For this reason, the present study was conducted to investigate the effect of phenylephrine on oxytocin-induced hemodynamic changes. This study was conducted on a group of pregnant women referred to Ayatollah Taleghani Hospital in Ilam and those undergoing cesarean section were included in the study. The objectives of the study explained to the women participating in the study, whether the participation was voluntary or not to participate in the intervention, compliance with the Helsinki and Belmont Declaration, and confidentiality of information. The women included in the study were randomly assigned to experimental and control groups. The checklists of the researchers were completed by observing and asking the patients from the time the patient entered the hospital until the end of the surgery. The variables expected by the researchers were evaluated before the intervention and 2, 4, 6, 8, 10 and 12 minutes after the intervention. In the experimental group, 12 (30%) patients had no nausea, 18 (45%) patients had low nausea, 8 (20%) patients had moderate nausea and 2 (5%) patients had severe nausea. While in the control group, 5 (12.5%) patients had no nausea, 13 (32.5%) patients had low nausea, 14 (35%) patients had moderate nausea and 8 (20%) patients had severe nausea. Also, a significant difference was between in the experimental and control groups in terms of nausea (P = 0.02). The study results showed that using phenylephrine can be effective on improving blood pressure, heart rate, nausea and vomiting in patients, which for this reason it is recommended to use this drug to improve the health of women undergoing cesarean section.