What medicine can you not take to donate blood? A guide to donor eligibility and medication deferrals

October 14, 2025 •

4 min read

According to the American Red Cross, most medications do not disqualify a person from donating blood. However, certain powerful drugs or those affecting blood function are a critical part of determining what medicine can you not take to donate blood. The deferral period varies based on the medication and is a safeguard for both the donor and the recipient.

Quick Summary

Donation eligibility is affected by specific drugs and medical conditions. Medications can cause permanent or temporary deferrals to protect both the donor and recipient, with specific waiting periods depending on the drug and the type of donation.

Key Points

Blood Thinners Are a Deferral: Medications like warfarin (Coumadin), Eliquis, and Xarelto cause a deferral to prevent excessive bleeding in the donor.
Certain Acne & Hair Loss Drugs Prohibit Donation: Powerful drugs such as isotretinoin (Accutane) and finasteride (Propecia) require waiting periods due to the risk of severe birth defects if transfused to a pregnant recipient.
HIV Prevention Medications Require a Waiting Period: Oral PrEP and PEP necessitate a 3-month waiting period, while injectable PrEP requires 2 years, as these can interfere with sensitive blood screening tests.
Aspirin Affects Platelet Donation Only: You can donate whole blood while on aspirin, but you must wait at least 48 hours to donate platelets due to its effect on platelet function.
Do Not Stop Prescribed Medications to Donate: It is unsafe and unnecessary to stop taking medication prescribed by a doctor just to donate blood. Eligibility is determined by the blood center.
Many Common Drugs Are Permitted: Birth control, most blood pressure medications, and Tylenol are usually acceptable for donation.
The Reason for the Medication is Key: Eligibility is often determined by the underlying medical condition requiring the medication rather than the drug itself.

Donating blood is a generous act, but for the safety of both the donor and the recipient, strict eligibility guidelines are in place. While many common medications are perfectly acceptable, others can cause a temporary or permanent deferral. The rules are not meant to discourage donation but to ensure the blood supply is as safe as possible for transfusion recipients, especially pregnant women, babies, and patients with compromised immune systems.

Why Medications Can Cause a Deferral

There are several key reasons why a medication might impact your ability to donate blood:

Protecting the Recipient

Some drugs can have a long-lasting effect and may pose a risk to a patient receiving the blood. For example, medications that cause severe birth defects, such as isotretinoin (Accutane) or dutasteride (Avodart), can be harmful to an unborn fetus if the donated blood is given to a pregnant woman. Similarly, certain antiviral medications used to prevent HIV can interfere with sensitive blood screening tests, leading to false-negative results. To protect the recipient, a waiting period is required to ensure these drug levels are no longer present in the bloodstream.

Protecting the Donor

Other medications, like anticoagulants or "blood thinners," affect the blood's ability to clot. For someone taking these drugs, the risk of excessive bleeding and bruising at the donation site is higher. These deferrals are a precaution for the donor's own safety during and after the blood collection process.

Affecting Blood Components

Some medications specifically impact certain blood components. The most common example is aspirin, which interferes with platelet function. While someone on aspirin can still donate whole blood, they must wait 48 hours to donate platelets, a component often used to help cancer patients and others with clotting issues.

Common Medications Requiring Deferral

Knowing the specific drugs that cause deferral is essential for anyone considering donating. Here are some of the most common categories and examples:

Blood Thinners (Anticoagulants)

These medications are used to prevent and treat blood clots. Because they increase the risk of bleeding for the donor, a waiting period is necessary.

Warfarin (Coumadin): 7-day deferral after the last dose.
Dabigatran (Pradaxa), Rivaroxaban (Xarelto), Apixaban (Eliquis): 2-day deferral after the last dose.
Heparin: 7-day deferral (often applies to plasma donation).

Acne and Psoriasis Medications

These drugs are teratogenic, meaning they can cause severe birth defects.

Isotretinoin (Accutane): 1-month deferral after the last dose.
Finasteride (Proscar, Propecia): 1-month deferral after the last dose.
Dutasteride (Avodart): 6-month deferral after the last dose.
Acitretin (Soriatane): 3-year deferral after the last dose.
Etretinate (Tegison): Permanent deferral.

HIV Prevention and Treatment Medications

For the safety of recipients, deferral periods are applied to individuals taking HIV prevention medications, while those on treatment are permanently deferred.

Oral PrEP/PEP (Truvada, Descovy): 3-month deferral from the last dose.
Injectable PrEP (Apretude): 2-year deferral from the last injection.
Antiretroviral Therapy (ART) for HIV: Permanent deferral.

Immunosuppressants and Other Powerful Drugs

Some medications used for autoimmune conditions or cancers also require deferral.

Mycophenolate mofetil (CellCept): 6-week deferral.
Thalidomide (Thalomid): 1-month deferral.

Antibiotics

Antibiotics taken for a current infection require a waiting period.

You must be finished with your course of oral antibiotics and symptom-free for at least 24 hours (or longer, depending on the infection).
Antibiotics taken for conditions like acne or as a preventative measure are generally acceptable.

Comparison of Key Medication Deferral Periods


Medication Category	Examples	Deferral Period	Primary Reason for Deferral
Anticoagulants	Warfarin (Coumadin)	7 days after last dose	Risk of excessive donor bleeding
	Rivaroxaban (Xarelto), Apixaban (Eliquis)	2 days after last dose	Risk of excessive donor bleeding
Antiplatelet Drugs	Aspirin	48 hours for platelet donation only; whole blood OK	Affects platelet function
Acne/Prostate	Isotretinoin (Accutane)	1 month after last dose	Potential birth defects if transfused to a pregnant woman
	Finasteride (Propecia, Proscar)	1 month after last dose	Potential birth defects if transfused to a pregnant woman
	Dutasteride (Avodart)	6 months after last dose	Potential birth defects if transfused to a pregnant woman
HIV Prevention	Oral PrEP/PEP	3 months after last use	May mask HIV and interfere with screening tests
HIV Treatment	Antiretroviral Therapy (ART)	Permanent deferral	Incomplete virus clearance; risk of transmission
Psoriasis	Acitretin (Soriatane)	3 years after last dose	Teratogenic effects

Donating Platelets vs. Whole Blood: Special Considerations

When donating platelets (a procedure called apheresis), specific antiplatelet medications become a factor. Aspirin, for example, is acceptable for whole blood donation but requires a 48-hour waiting period before donating platelets. Medications like clopidogrel (Plavix) also require a waiting period of up to 14 days before platelet donation. This is because these drugs prevent platelets from clumping, making them ineffective for patients who need functioning platelets for clotting.

Many Common Medications Are Acceptable

It's important to remember that most routine medications do not prevent you from donating blood. This includes:

Oral contraceptives
Most blood pressure medications
Cholesterol medications
Thyroid medications
Vitamins and herbal supplements
Acetaminophen (Tylenol) and ibuprofen (Advil) for whole blood donation
Antidepressants

Conclusion

Understanding what medicine can you not take to donate blood is crucial for donor safety and the integrity of the blood supply. The most critical takeaway is to never stop a prescribed medication in order to donate blood. If you are taking medication, the best course of action is to check the specific guidelines with your local blood center, such as the American Red Cross, or use their online resources before your appointment. With some simple preparation, many individuals can contribute to this life-saving cause.

For a detailed list of eligible medications and conditions, you can visit the American Red Cross website.

Frequently Asked Questions

Yes, in most cases. As long as your blood pressure is well-controlled and within the acceptable range on the day of donation, taking blood pressure medication is not a cause for deferral.

You must wait 1 month after your last dose of isotretinoin (Accutane) before you can donate blood. This is due to the risk of birth defects if the blood is transfused to a pregnant patient.

Not for whole blood donation. However, you must wait at least 48 hours after taking aspirin or any aspirin-containing medication before donating platelets.

Yes. The majority of antidepressants do not prevent you from donating blood, provided you are feeling well and your underlying condition is stable.

You must complete your course of antibiotics and be symptom-free from the infection for at least 24 hours. The specific waiting period may vary depending on the reason for the antibiotic.

You must wait 3 months after your last oral dose of PrEP/PEP or 2 years after your last injectable dose before you can donate. This is to ensure accurate blood screening results.

Yes. Medications like etretinate (Tegison) for psoriasis and any type of antiretroviral therapy (ART) for HIV result in a permanent deferral.