Objective Methamphetamine use disorder (MUD) is a global health condition that impairs a person’s health which may result in morbidity and mortality. Inflammation is a crucial process playing a vital role in MUD. For this reason, it is necessary to examine biochemical parameters for follow-up and treatment alternatives.Methods We aimed to reveal the relationship between inflammatory response and MUD by evaluating peripheral hemogram parameters, leukocyte count, subtypes, and their ratios to each other, systemic immune inflammation index (SII), monocyte/high-density lipoprotein (HDL) ratio, and human C-reactive protein (CRP) in adult men with MUD. We included 76 adult male participants in the patient group and 70 adult male participants in the control group. We calculated the neutrophil/lymphocyte rate (NLR), monocyte/lymphocyte rate (MLR), platelet/lymphocyte rate (PLR), and basophil/lymphocyte rate (BLR). In addition, we obtained the SII and the monocyte/HDL rate.Results The patients’ leukocyte (p<0.001), platelet (p<0.001), plateletcrit (PCT) (p=0.002), neutrophil (p<0.001), monocyte (p=0.002), CRP (p<0.001), NLR (p=0.001), PLR (p=0.004), MLR (p=0.009), SII (p<0.001) and monocyte/HDL ratio (p<0.001) were higher than the control group. We observed a significant and positive relationship between the daily methamphetamine intake, and methamphetamine use duration (p=0.002), PCT (p=0.044), neutrophil (p=0.021), NLR (p=0.001), PLR (p=0.004), MLR (p=0.029), and SII (p<0.001). Daily methamphetamine intake had a significant and positive effect on SII. A one-unit increase in daily methamphetamine intake elevated SII by 165.53 units.Conclusion The results confirm the presence of peripheral subclinical inflammation and systemic immune inflammation in adult men with MUD.