Inhalation of a gas anesthetic produces rapid induction of anesthesia without the need for intravenous drugs. Although it is specifically useful for patients who are afraid of injections or if their intravenous access is difficult, single-breath induction may also allow patients to wake up more quickly than intravenous induction drugs. The object of this study is to compare isoflurane and sevoflurane during inhalation in Libyan patients undergoing surgery in terms of side effects like blood pressure and heart rate changes and complications. Seventy- five patients were recruited in this study from different hospitals in Benghazi City, Libya (January to March 2022) including Aljalaa Hospital and Alatfal Hospital, and data including side effects and complications were collected through data collection. Surgeries that used isoflurane, or sevoflurane or both inhalation gases for anesthesia were included in our data. While the surgeries that did not use any of these inhalation gases were excluded from our data. When we compared the side effects of using isoflurane with sevoflurane according to the age group, we found that hypotension is the most common side effect compared to the use of isoflurane in our adult population (28.6%) and in pediatrics (14.3%) but there was a low incidence of other side effects related to sevoflurane administration. Regarding to side effects related to the use of sevoflurane according to the age groups, 16 adult Libyan patients experienced no side effects (61.5%) compared to 10 children (38.5%). It can be concluded that both isoflurane and sevoflurane are suitable for daycare anesthesia. Sevoflurane might be an ideal drug for single-breath inhaled induction of anesthesia due to it has fewer side effects and complications.