What are the guidelines for administering intramuscular (IM) steroid injections to patients on anticoagulation therapy, including those on warfarin (Coumadin) and direct oral anticoagulants (DOACs)?

IM Steroid Injections in Anticoagulated Patients

Intramuscular injections, including IM steroid injections, should be avoided in patients receiving anticoagulation therapy and alternative routes (oral or intravenous) should be used instead. 1

Primary Guideline Recommendation

The American Heart Association explicitly states that intramuscular injections should be avoided in patients who are receiving anticoagulant therapy (Class I, Level of Evidence A). 1 This represents the strongest level of recommendation with high-quality evidence supporting avoidance of the IM route in this population.

Alternative Administration Routes

When IM injections are contraindicated due to anticoagulation:

• Orally administered regimens should be given whenever possible in patients on anticoagulants 1
• Intravenously administered medications should be used for patients who are unable to tolerate or absorb oral medications 1

This guidance applies to all patients on anticoagulation, including:

• Warfarin (vitamin K antagonists) 1
• Direct oral anticoagulants (DOACs: dabigatran, rivaroxaban, apixaban, edoxaban) 1
• Heparin products 1

Evidence on Bleeding Risk

While recent observational data suggests that bleeding complications at IM injection sites among anticoagulated hospitalized patients are rare (0.02%), 2 the guideline-based recommendation to avoid IM injections in anticoagulated patients remains the standard of care. 1 The retrospective study found only 2 verified injection site bleeding complications among 8,189 anticoagulated patients receiving IM injections, 2 but this does not override the established guideline recommendation to avoid this route when alternatives exist.

Clinical Decision Framework

For patients requiring steroid administration while on anticoagulation:

1. First choice: Oral corticosteroids (prednisone, methylprednisolone, dexamethasone) 1
2. Second choice: Intravenous corticosteroids if oral route is not feasible due to inability to swallow, absorb, or tolerate oral medications 1
3. Avoid: IM steroid injections regardless of anticoagulation type (warfarin, DOACs, or heparin) 1

Important Caveats

• This recommendation applies to all anticoagulant classes equally - there is no distinction made between warfarin, DOACs, or heparin products in terms of avoiding IM injections 1
• The strength of this recommendation (Class I, LOE A) indicates this is not a situation where clinical judgment should override the guideline - alternatives should always be sought 1
• Even if INR is therapeutic or subtherapeutic on warfarin, the IM route should still be avoided 1