Plasma donation, a process called plasmapheresis, involves drawing blood, separating the liquid plasma component using a specialized machine, and returning the remaining blood cells to the donor’s body. This straw-colored fluid contains vital proteins, antibodies, and clotting factors that are irreplaceable for treating numerous serious conditions. The collected plasma, known as source plasma, is fractionated to create life-saving therapies for patients with immune deficiencies, bleeding disorders, and severe burn injuries. Because the plasma becomes a medicinal product administered to vulnerable patients, a rigorous screening process, including a review of all medications, is a mandatory safety measure.
The Safety Rationale Behind Medication Screening
The requirement to disclose all prescription and over-the-counter medications is rooted in two distinct safety concerns: protecting the donor’s health and safeguarding the recipient’s well-being. Certain drugs can interfere with the physical process of donation, directly posing a risk to the individual. For example, medications that affect blood clotting can increase the chance of excessive bleeding or bruising during the plasmapheresis procedure.
Other medications are screened because residual amounts could remain in the donated plasma and potentially compromise the health of the patient receiving the final manufactured therapy. A drug that is harmless to the donor might cause an adverse reaction in a recipient who is already immunocompromised. Furthermore, some drug deferrals are not about the medication itself but rather the underlying medical condition it is being used to treat, which may pose a risk of disease transmission.
Medications Requiring a Temporary Waiting Period
Many common medications only require a brief waiting period, or deferral, which is determined by the drug’s half-life and the reason it was taken.
Antibiotics typically result in a temporary deferral to ensure the donor is fully recovered from the infection, usually requiring a wait of 24 hours to three days after the last dose, along with the complete resolution of symptoms. This waiting period confirms the donor is no longer experiencing a systemic illness that could affect the quality of the plasma.
Anti-platelet medications, such as aspirin, are a common cause of temporary deferral. While a low dose of aspirin may only require a 48-hour wait, other anti-platelet drugs like clopidogrel (Plavix) can necessitate a 14-day deferral because of their prolonged effect on platelet function. Anticoagulants, often called blood thinners, also have specific deferral periods to protect the donor from complications related to the needle stick during the procedure. Newer oral anticoagulants like rivaroxaban (Xarelto) may require a two-day wait, while older medications like warfarin (Coumadin) necessitate a seven-day period before donation.
Certain medications prescribed for skin conditions or benign prostatic hyperplasia (BPH) require time-specific deferrals because of their potential to cause severe birth defects if transfused into a pregnant recipient. The potent acne treatment isotretinoin (Accutane) requires a 30-day waiting period following the last dose. Similarly, finasteride, a drug used for hair loss or BPH, also carries a mandatory 30-day deferral period due to the risk of fetal harm.
Vaccines also fall under temporary deferral guidelines, though the waiting time varies based on the type of vaccine administered. Inactivated or synthetic vaccines, such as those for influenza or tetanus, usually do not require any deferral period. However, live-attenuated virus vaccines, like those for measles, mumps, rubella, or varicella, require a longer observation period, often two to four weeks, to confirm the donor does not develop a transmissible subclinical infection.
Medications Resulting in Indefinite Deferral
A smaller group of medications results in an indefinite or permanent deferral, often because the drug’s use signals an underlying, long-term health condition that prohibits donation.
Antiviral medications used to treat chronic viral infections, such as Human Immunodeficiency Virus (HIV) or Hepatitis C, result in indefinite deferral. The infectious disease poses a direct and unacceptable risk of transmission through the plasma product, making the medication itself less of a concern.
Powerful immunosuppressive agents, particularly those used following an organ or tissue transplant, also lead to permanent deferral. This restriction is primarily related to the transplant history and the underlying need for immune suppression, which can compromise the donor’s health during the procedure. The presence of these systemic conditions is the primary cause of ineligibility.
Some retinoid medications used for severe skin conditions carry much longer waiting periods or indefinite deferrals. For instance, acitretin, a drug for psoriasis, requires a three-year deferral period after the last dose due to its extremely long half-life and teratogenic risk. A related drug, etretinate, results in an indefinite deferral because its residue can persist in the body for decades.
Furthermore, a specific and historic deferral exists for people who received certain pituitary-derived growth hormone injections or bovine insulin products between 1980 and 1996. These individuals are permanently deferred from donation due to a theoretical risk of transmitting Creutzfeldt-Jakob disease.