laboratory event in methotrexate monitoring
Last reviewed 01/2018
| Event | Value | Action |
| Leucopaenia | <3.5*10^9/l | Stop & seek advice |
| Neutropaenia | <2.5*10^9/l | Stop & seek advice |
| Thrombocytopaenia | <150*10^9/l | Stop & seek advice |
| Macrocytosis | >100 | Macrocytosis >100 Check B12 and folate |
| Sequential falls in WCC or PMNs | >10% on occasions | Stop & seek advice |
| Sequential falls in platelets | Sequential falls >10% on 3 occasions | Stop unless falls are from in platelets from a high level, which is a response to treatment |
| Elevation of LFTs (AST, ALT, not ALP) | >3x normal | Stop & repeat LFTs (AST, ALT, not ALP) Mild transaminitis is common |
| Falls in albumin | >5g/l | Stop. Repeat LFTs. (early sign of liver toxicity) |