General dosing guidelines

Please see the attached document for dosing guidelines for LMWHs at UW Medicine.

NOTE:  anectodal clinical and pharmacokinetic evidence at UW Medicine dating back to the early 1990s suggests that the clearance of enoxaparin is compromised in the presence of the calcineurin inhibitors (CNI) cyclosporine and tacrolimus.  It is our practice to reduce full dose enoxaparin by one level (from 1mg/kg SQ q12h to 0.85mg/kg SQ q12h, or from 0.85mg/kg SQ q12h to 1mg/kg SQ q24h) in patients on concurrent CNI therapy. 

Simplified nomogram for warfarin maintenance dosing

Goal INR 2-3  

Goal INR 2.5-3.5

<2 Reload x 0-1
Increase by 5-15%
2-3 No change 2.5-3.5
3.1-3.5 Decrease by 0-15% 3.6-4
3.6-4 Hold 0-1 dose
Decrease by 5-15%
>4 Hold until therapeutic
+/- minidose vitamin K
Decrease by 10-20%











Adapted from Crowther MA, Harrison L, Hirsch L. Ann Intern Med 1997; 127:332-3


Warfarin initiation dosing

Flexible Initiation Method

  • This nomogram is useful in hospitalized patients in whom INR can be checked on a daily basis.
  • Several studies have confirmed that 5mg initiation achieves therapeutic anticoagulation as rapidly as 10mg initiation but with a lower frequency of supra-therapeutic INRs.
  • The 10mg initiation nomogram should only be used in relatively young and healthy patients who are likely to be insensitive to warfarin, or in patients taking concurrent medications known to induce warfarin metabolism.
  • Please note that loading doses of warfarin are NOT RECOMMENDED.
    5mg Initiation 10mg Initiation
Day INR Dose Dose
1 - 5mg 10mg
2 <1.5 5mg 7.5-10mg
1.5-1.9 2.5mg 2.5mg
2-2.5 1-2.5mg 1-2.5mg
>2.5 0 0
3 <1.5 5-10mg 5-10mg
1.5-1.9 2.5-5mg 2.5-5mg
2-2.5 0-2.5mg 0-2.5mg
2.5-3 0-2.5mg 0-2.5mg
>3 0 0
4 <1.5 10mg 10mg
1.5-1.9 5-7.5mg 5-7.5mg
2-3 0-5mg 0-5mg
>3 0 0
5 <1.5 10mg 10mg
1.5-1.9 7.5-10mg 7.5-10mg
2-3 0-5mg 0-5mg
>3 0 0
6 <1.5 7.5-12.5mg 7.5-12.5mg
  1.5-1.9 5-10mg 5-10mg
  2-3 0-7.5mg 0-7.5mg
  >3 0 0