Dextromethorphan, Memantine Monotherapy, or Combined Use of Dextromethorphan and Memantine in Amphetamine Addiction

Inclusion Criteria:

1. Signed informed consent by patient or legal representative.
2. Male or female patient aged ≧20 and ≦65 years.
3. A diagnosis of ATSUD according to DSM criteria made by a specialist in psychiatry.
4. Patient or a reliable caregiver can be expected to ensure acceptable compliance andvisit attendance for the duration of the study.

Exclusion Criteria: The presence of any of the following will exclude a patient from study enrollment:

1. Women of childbearing potential, not using adequate contraception as per investigatorjudgment or not willing to comply with contraception for the duration of the study.
2. Females who are pregnant or lactation.
3. Other major Axis-I DSM-IV diagnosis other than ATSUD, except for tobacco use disorder,ATS induced mood or psychotic disorders.
4. Current evidence of an uncontrolled and/or clinically significant medical condition,e.g., cardiac, hepatic and renal failure that would compromise patient safety orpreclude study participation.
5. History of allergy or intolerable side effects of DM or MM.
6. Suicidal attempts or risks during screen or study period.
7. Presence of active infectious or autoimmune disease.