What medications are contraindicated for blood donation?

Medications Contraindicated for Blood Donation

The primary medications that absolutely contraindicate blood donation are teratogenic drugs (retinoids, thalidomide, lenalidomide, dutasteride, finasteride), genotoxic drugs, and irreversible platelet inhibitors within specific timeframes, while most other medications require only brief deferral periods based on their pharmacokinetic properties. 1

Absolute Contraindications

Teratogenic Medications

• Retinoids (isotretinoin, acitretin), thalidomide, and lenalidomide require deferral periods for ALL blood products due to severe teratogenic risk to potential recipients of childbearing age 1
• Dutasteride and finasteride similarly require waiting periods for all blood product donations 1
• These medications pose unacceptable risks even in trace amounts that might be present in blood products 1

Genotoxic Drugs

• Any genotoxic medication requires a deferral period of t(max) + 24 half-lives for every blood product type 1
• This extended waiting period accounts for the potential mutagenic effects on recipients 1

Antiplatelet Agents (Context-Specific)

• Irreversible platelet function inhibitors (aspirin, clopidogrel, prasugrel, ticagrelor, ticlopidine) require a 10-day waiting period specifically if platelet concentrate production is intended 1, 2
• For other blood products (red blood cells, plasma), these medications do not require deferral 1
• The 10-day period allows for adequate platelet regeneration, which occurs at 10-15% per day 2

Conditional Contraindications Based on Blood Product Type

Anticoagulants

• Warfarin, clopidogrel, and aspirin require discontinuation with waiting periods of t(max) + 5 half-lives for blood products containing >50 mL single-donor plasma 1, 2
• For red blood cell concentrates containing <50 mL plasma intended for adult recipients, no deferral period is necessary 1
• Clopidogrel effects last approximately one week 2
• Warfarin effects persist for several days depending on patient response 2

Direct Oral Anticoagulants (DOACs)

• Dabigatran, rivaroxaban, apixaban, and edoxaban require deferral periods calculated as t(max) + 5 half-lives for plasma-containing products 1
• These agents have shorter half-lives (5-13 hours for factor Xa inhibitors, 48-72 hours for dabigatran with normal renal function) compared to warfarin 2

Low Molecular Weight Heparins (LMWH)

• Enoxaparin, dalteparin, and other LMWHs require brief deferral periods based on their pharmacokinetics 1
• The active metabolites of these drugs circulate for limited periods after the last dose 2

Medications That Do NOT Contraindicate Donation

Drugs Without Systemic Effects

• Topical medications, inhaled medications, and drugs without systemic absorption can be neglected and do not require deferral 1

Drugs with Dose-Dependent Pharmacodynamics

• For most medications with predictable dose-response relationships, no deferral periods are necessary for blood products containing <50 mL single-donor plasma when used in adults 1
• This includes many common medications like antihypertensives, antibiotics, and other routine therapies 1

Practical Algorithm for Donor Eligibility

Step 1: Identify Medication Class

• Determine if the medication is teratogenic, genotoxic, antiplatelet, anticoagulant, or has only local effects 1

Step 2: Determine Blood Product Type

• Products with <50 mL single-donor plasma (red blood cell concentrates) have minimal restrictions 1
• Products with higher plasma content (fresh frozen plasma, platelet concentrates) require more stringent evaluation 1

Step 3: Calculate Deferral Period

• For teratogenic drugs (retinoids, thalidomide, lenalidomide, dutasteride, finasteride): Extended deferral for all products 1
• For genotoxic drugs: t(max) + 24 half-lives 1
• For anticoagulants/antiplatelets: t(max) + 5 half-lives for plasma-containing products; 10 days for platelet concentrates 1, 2
• For other medications: Generally no deferral for low-plasma products 1

Common Pitfalls to Avoid

Overly Restrictive Deferral

• Do not unnecessarily defer donors on common medications when donating red blood cell concentrates for adult recipients, as the plasma content is minimal and poses negligible risk 1
• Many donors can safely donate despite being on routine medications 1

Insufficient Waiting Periods for High-Risk Drugs

• Never allow donation from patients on teratogenic or genotoxic drugs without appropriate extended deferral periods, as even trace amounts can cause harm 1
• The consequences of inadequate deferral for these medications are severe 1

Platelet Concentrate Production

• Always verify the intended use of the donation before accepting donors on antiplatelet agents, as a 10-day deferral is mandatory if platelet concentrates will be produced 1, 2
• This is the most commonly overlooked restriction 1