Objectives: Non-nutritional sources of sodium are commonly encountered in hospitalized patients who are used carbapenems to treat non-carbapenemase producing multi-drug resistant gram-negative bacteria. Meropenem and Imipenem/Cilastatin are the most two widely used carbapenems in most medical centers including our institution. The non-nutritional sources of sodium from both tested carbapenems may have a detrimental effect on critically ill patient’s organ functions and may be an independent risk factor for mortality. The primary objective of our study is to investigate the significance difference of non-nutritional associated hypernatremia (NNAH) risk between Meropenem (Group I) versus Imipenem/Cilastatin (Group II). Methods: Our study was retrospectively carried out for critically ill patients admitted to King Hussein Medical Hospital (KHMH) wards between April 2017 and Dec 2019 Patients were excluded if they discharged or died before completed 2 days of the tested ABs during their admission. Collected continuous data were analyzed using Independent T-Test while Chi Square Test were used for dichotomous data analysis and to determine the NNAH risk in both tested groups. Corrected sodium level (cNa+) level of 145 mEq/l will be considered the cutoff point for hypernatremia. Results: The mean overall age was 59.62±1.59 years, and 57 subjects (71.25%) were male. The overall risk of NNAH was 5.1% (4 patients). Critically ill patients who were on Meropenem had the highest risk of NNAH (7.9%, 3 patients) contrast on Imipenem /Cilastatin (2.4%, 1 patient).Conclusion: Our results demonstrate that empirical or targeted use of β-lactam Carbapenems either Meropenem or Imipenem/Cilastatin is an independent risk of NNAH especially in case of high dose Meropenem.