A Study to Evaluate the Effects of Lithium, Valproic Acid, and Lamotrigine on the Pharmacokinetics of KarXT and Effects of KarXT on the Pharmacokinetics of Lithium, Valproic Acid, and Lamotrigine in Healthy Participants

Inclusion Criteria: * Healthy male and female \[individual not of childbearing potential (INOCBP)\] participants as determined by no clinically significant deviation from normal in medical history, physical examination, 12-lead ECG, vital signs, and clinical laboratory determinations. * BMI of 18.0 to 32.0 kg/m2, inclusive. Exclusion Criteria: * History or presence of clinically significant cardiovascular, pulmonary, hepatic, renal, hematologic, GI, endocrine, immunologic, dermatologic, neurologic, or oncologic disease or any other condition that, in the opinion of the investigator, would jeopardize the safety of the participant or the validity of the study results. Note: Any grade of hepatic impairment (Child-Pugh Grade A or higher) is excluded. * Parts B and D only: History of pancreatitis. * Any significant acute or chronic medical illness, in the opinion of the investigator. * History or high risk of urinary retention, gastric retention, or narrow-angle glaucoma or known history of prostate hypertrophy or nocturia. * Parts E \& F only: history of skin rash and mucus ulcerations of no obvious cause and Gilbert's syndrome * Other protocol-defined Inclusion/Exclusion criteria apply.