To investigate the safety, tolerability, pharmacokinetics (including dose proportionality assessment), and pharmacodynamics of single rising oral doses of BI 1181181 (Single rising dose (SRD) part) Secondly, to investigate the relative bioavailability of the tablet versus the powder for oral solution (PfOS) and the effect of food on the pharmacokinetics of BI 1181181 (Bioavailability/Food effect (BA/FE) part)

Inclusion criteria:

• Healthy males according to the investigator's assessment, as based on the following criteria: a complete medical history including a physical examination, vital signs blood pressure (BP), pulse rate (PR), 12-lead ECG, and clinical laboratory tests
• Age 18 to 50 years (incl.)
• Body mass index (BMI) 18.5 to 29.9 kg/m2 (incl.)
• Signed and dated written informed consent prior to admission to the study in accordance with GCP and local legislation

Exclusion criteria:

• Any finding in the medical examination (including BP, PR or ECG) deviating from normal and judged clinically relevant by the investigator
• Repeated measurement of systolic blood pressure < 90 mmHg and >= 140 mmHg at screening
• Repeated measurement of diastolic blood pressure < 55 and >= 90 mmHg at screening
• Repeated measurement of pulse rate < 50 bpm and > 90 bpm at screening
• Any laboratory value outside the reference range that the investigator considers to be of clinical relevance
• Any evidence of a concomitant disease judged clinically relevant by the investigator
• Gastrointestinal, hepatic, renal, respiratory, cardiovascular, metabolic, immunological or hormonal disorders