| M1A.261 | Drug-induced chronic gout, right knee | NON-BILLABLE CODE |
| M1A.2610 | Drug-induced chronic gout, right knee, without tophus (tophi) | BILLABLE CODE |
| M1A.2611 | Drug-induced chronic gout, right knee, with tophus (tophi) | BILLABLE CODE |
| M1A.262 | Drug-induced chronic gout, left knee | NON-BILLABLE CODE |
| M1A.2620 | Drug-induced chronic gout, left knee, without tophus (tophi) | BILLABLE CODE |
| M1A.2621 | Drug-induced chronic gout, left knee, with tophus (tophi) | BILLABLE CODE |
| M1A.269 | Drug-induced chronic gout, unspecified knee | NON-BILLABLE CODE |
| M1A.2690 | Drug-induced chronic gout, unspecified knee, without tophus (tophi) | BILLABLE CODE |
| M1A.2691 | Drug-induced chronic gout, unspecified knee, with tophus (tophi) | BILLABLE CODE |
