Why Was I Deferred? Common Deferral Reasons Explained

What is a deferral?

A deferral means you've been temporarily or permanently disqualified from donating plasma at the time of your visit. Temporary deferrals end after a specific period; permanent deferrals mean you cannot donate in the future.

Most common deferral reasons

Low protein

Centers require a minimum protein level (typically 6.0 g/dL). Low protein is usually caused by insufficient protein intake, being sick, or dehydration. This is a temporary deferral — usually just a few days.

What to do: Increase protein intake with meals, hydrate well, and try again.

Low hematocrit (low iron)

Hematocrit measures the percentage of red blood cells in your blood. Centers require a minimum level. Low hematocrit can be from iron deficiency, menstruation, or poor diet.

What to do: Eat iron-rich foods for a week, and try again. Consider speaking with your doctor if this is a recurring issue.

High blood pressure

Centers typically require systolic blood pressure below 180 and diastolic below 100. High readings are sometimes due to anxiety ("white coat effect") or temporary elevations.

What to do: Try to relax before your next visit, reduce caffeine and sodium intake, and ask if you can have your blood pressure re-taken.

Recent tattoo or piercing

Most centers require a 4-month waiting period after tattoos or piercings received in unlicensed shops. Many states have exceptions for licensed parlors.

Medication deferral

Some medications defer you from plasma donation due to their effects on recipients. The most notable include blood thinners, certain antibiotics, and medications containing growth hormones.

Illness

Any active illness, fever, or cold symptoms will defer you temporarily — usually until 2 weeks after full recovery.