This study is a single-dose, randomized, open-label, three-sequence, three-period crossover clinical trial to evaluate the effect of high-fat and low-fat meals on the pharmacokinetics of ammoxetine hydrochloride enteric-coated tablets in healthy subjects.

Inclusion Criteria:

1. Age: 18-45 years (inclusive), both male and female subjects;
2. Body weight ≥ 45.0 kg (female) or 50.0 kg (male), with body mass index (BMI) between 19.0 kg/m² and 28.0 kg/m² (inclusive);
3. Results of medical history, vital signs, physical examination, laboratory tests (including complete blood count, blood biochemistry, urinalysis, coagulation function, and other relevant tests), and chest X-ray examination are normal or abnormal but without clinical significance;
4. Subjects with corrected QT interval using Fridericia's formula exceeding the upper limit of normal (male ≥450 ms or female ≥460 ms), or with abnormal electrocardiogram findings considered clinically significant by the study physician, or with a history of arrhythmias or syncope associated with arrhythmias, or using a pacemaker.
5. Voluntarily sign the informed consent form and be willing to comply with the protocol to complete the study.

Exclusion Criteria:

1. Subjects with a history of allergies (allergic to two or more types of drugs, foods, or pollen);
2. Subjects suffering from psychiatric disorders, hepatic or renal diseases, gastrointestinal diseases, neurological diseases, or other systemic diseases;
3. Subjects with orthostatic hypotension;
4. Subjects with a 12-lead ECG QTcF interval exceeding the upper limit of normal (male ≥450 ms or female ≥460 ms), or with abnormal ECG findings considered clinically significant by the study physician, or with a history of arrhythmias or syncope associated with arrhythmias, or using a pacemaker. Note: Diseases include, but are not limited to: heart failure; hypokalemia; atrial fibrillation, atrial flutter, premature atrial contractions, premature ventricular contractions, non-sustained or sustained ventricular tachycardia; bradycardia or sick sinus syndrome; personal or family history of any cardiac conduction abnormalities; personal or family history of long QT syndrome (LQTS); or family history of sudden death;
5. Subjects with a history of smoking or alcohol abuse (consumption of 14 units of alcohol per week within the 4 weeks prior to screening: 1 unit = 285 mL beer, or 25 mL spirits, or 150 mL wine; daily smoking ≥ 5 cigarettes) or other substance or drug abuse within the past year;
6. Subjects with a positive alcohol breath test or positive urine drug screen during the screening period;
7. Subjects who have donated or lost more than 400 mL of blood within the 8 weeks prior to screening;
8. Subjects who have participated in other drug clinical trials within the 3 months prior to screening;
9. Subjects who habitually consume excessive amounts of caffeinated beverages or foods within the 4 weeks prior to screening, such as coffee, tea, chocolate, cola, or Red Bull (daily caffeine intake not exceeding 6 units). 1 caffeine unit = 1 cup of coffee (177.4 mL) = 2 cans of cola (354.9 mL) = 1 cup of tea (354.9 mL) = 1/2 cup of energy drink = 85 g chocolate;
10. Subjects who have used medications that alter the activity of liver enzymes (Cytochrome P450 2C19 and Cytochrome P450 3A4) within the 4 weeks prior to screening, such as dexamethasone, ketoconazole, rifampicin, or omeprazole;
11. Subjects who have consumed dragon fruit, mango, shaddock, grapefruit, lime, star fruit, pomegranate, or any foods or beverages prepared from these fruits within the 7 days prior to screening;
12. Subjects who have used prescription drugs, over-the-counter medications (except for occasional use of acetaminophen and nasal sprays), herbal remedies, vitamins, or minerals within the 2 weeks prior to screening, or for whom the washout period of prior medications (based on the longest half-life) is less than 5 half-lives before screening;
13. Subjects using any psychiatric medications or psychoactive substances;
14. Pregnant or lactating women, or female subjects with a positive pregnancy test during the screening period;
15. Subjects considered by the investigator to have any factors that make them unsuitable for participation in this trial.