Plasma is the pale, straw-colored liquid component of blood that makes up over half of its volume. This complex fluid carries water, salts, enzymes, antibodies, and proteins throughout the body. Donated plasma is processed to create life-saving therapeutic products used to treat conditions such as immune deficiencies, hemophilia, and severe burns. The safety of these products depends on the rigorous health screening and honesty of every donor.
Screening vs. Toxicology Testing
Plasma centers generally do not conduct a dedicated, lab-based toxicology screening for common recreational drugs, such as a urine or blood test. Unlike employment or probation screenings, the process is not focused on identifying drug metabolites. The primary goal of the initial screening is to assess the donor’s immediate fitness for the plasmapheresis procedure and to ensure the quality of the donated material.
Centers rely heavily on a detailed medical history questionnaire and a physical examination conducted by trained staff. The questionnaire asks direct questions about drug use, which donors must answer truthfully. Staff observe the donor for outward signs of intoxication, such as slurred speech or impaired coordination, because a donor cannot legally consent while under the influence. The physical exam includes a visual inspection of the arms for signs of intravenous drug use, a behavior that poses a high risk for bloodborne diseases.
Drug Use Deferral Criteria
Although a formal toxicology screen is absent, a history of drug use is a major factor in determining eligibility, leading to temporary or permanent deferral. The most strict rule concerns intravenous (IV) drug use, which is a permanent disqualifier for plasma donation. This deferral is based on the extremely high risk of transmitting serious bloodborne pathogens, such as HIV and Hepatitis, which are frequently associated with shared needles.
Non-IV drug use can lead to a temporary deferral if it is recent (often within the last three months) or if the donor exhibits signs of impairment during screening. For substances like marijuana, use is generally not an automatic disqualifier if the donor is not intoxicated at the time of donation. Alcohol consumption or visible intoxication on the day of donation results in an immediate deferral, ensuring the donor is fully capable of consenting to the procedure.
The abuse of prescription medications or their use outside of a doctor’s guidance can result in a deferral, depending on the specific drug. Certain non-abused prescription medications, particularly those that affect blood clotting or the immune system, may also temporarily or permanently disqualify a person. The deferral criteria are complex and designed to protect the donor’s health during the procedure and the safety of the final therapeutic products.
Mandatory Infectious Disease Testing
While centers do not test for recreational drugs, every unit of donated plasma is subjected to mandatory laboratory tests required by regulatory bodies like the U.S. Food and Drug Administration (FDA). These tests focus exclusively on identifying infectious agents that could be passed to a recipient. This required testing ensures the product is safe for manufacturing into plasma-derived therapies.
All plasma units are tested for evidence of infection from communicable disease agents, including Hepatitis B, Hepatitis C, and HIV-1/2. Testing often includes checks for other agents, such as West Nile Virus, depending on current risk levels. These tests are performed on a sample collected at the time of donation, and the donation cannot be released until results confirm it is free of pathogens.
A small blood sample is also analyzed to assess the donor’s overall health and the quality of the plasma itself. This mini-screening checks the donor’s hematocrit level to ensure they are not anemic and can safely donate. It also checks the total protein level, which indicates the plasma’s quality and the donor’s overall nutritional status.