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Frequently Asked Questions

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Why Platelets Matter
What do platelets actually do?
Platelets are small cell fragments that clump together at the site of an injury and form the initial plug that stops bleeding. Without enough of them — or with platelets that do not work properly — even minor bleeding can become dangerous, and spontaneous bleeding can start with no injury at all.
Who receives donated platelets?
Cancer patients are the largest group, close to half of all recipients. Chemotherapy and radiation suppress the bone marrow that produces platelets, so people undergoing treatment for leukemia, lymphoma, and other cancers often need repeated transfusions over weeks or months. Others include stem cell and organ transplant recipients, patients with aplastic anemia and other marrow disorders, trauma and burn victims, people undergoing major or cardiac surgery, and premature infants.

Most platelet transfusions are given preventively, to a patient who is not bleeding but whose count has fallen low enough that a hemorrhage becomes likely.

Why is platelet donation done separately instead of taken from whole blood?
Because a single pint of whole blood contains only a small fraction of an adult dose. Collecting platelets by apheresis lets one donor provide a full therapeutic dose in one sitting — roughly the equivalent of four to six whole blood donations' worth of platelets. At Fountain Bio, we aim for donors with characteristics able to yield at least two or three separate doses.

The more important advantage is for the patient. A pooled dose made from whole blood exposes the recipient to four to six different donors; an apheresis dose exposes them to one. For a leukemia patient receiving dozens of transfusions, that difference in donor exposures matters considerably. This is why roughly 97 to 98 percent of platelets transfused in the United States now come from apheresis donors rather than from pooled whole blood.
How does platelet donation compare with giving whole blood?
Comparison of platelet, whole blood, and double red cell donations
FeaturePlateletsWhole BloodDouble Red Cells
What is collectedPlatelets only; red cells and most plasma are returnedOne pint of whole bloodTwo units of red cells; the rest returned
Time on siteAbout 2 to 3 hoursAbout 1 hourAbout 1.5 hours
How oftenEvery 11 days, up to 24 a yearEvery 56 days, up to 6 a yearEvery 112 days, up to 3 a year
Iron lossMinimalMeaningfulSubstantial
Aspirin restrictionYesNoNo
Why do blood centers ask platelet donors to come back so often?
Because platelets cannot be stockpiled. A platelet unit is good for five to seven days from collection. There is no way to build a reserve ahead of a busy week.
Am I Eligible?
What are the basic requirements?
You must be in good general health, weigh at least 110 pounds, meet the hemoglobin minimums (12.5 g/dL for female donors and 13.0 g/dL for male donors), and have a platelet count of at least 150,000 per microliter. Our accepted age range for platelet donation is between 18 and 75 years old. You will need proper identification and must complete a health history questionnaire.
How is my platelet count measured, and what if it is low?
A complete blood count (CBC) will be performed on samples collected at your initial pre-screening and at subsequent visits. Fountain Bio requires a platelet count of at least 150,000 per microliter to donate. Final eligibility is based on your platelet count in relation to your weight. If your calculated platelet yield is insufficient, you will be placed on a permanent deferral and will not be able to donate.
I passed the hemoglobin check before. Can I still be turned away from platelets?
Yes, your hemoglobin level must be at least 12.5 g/dL for females and 13.0 g/dL for males to donate. If it is below, you may be deferred for a period of time. Staff can discuss steps to help increase your levels.
Why do my veins matter more for platelets?
Because the needle has to stay seated and flowing well for 70 to 120 minutes rather than the 8 to 10 minutes a whole blood draw takes. In single-needle procedures, the same vein handles both the draw and the return.
I have been pregnant. Can I donate platelets?
If you are currently pregnant or breastfeeding, you are not eligible. If you have been pregnant in the past, you may donate after a test. Pregnancy can cause the body to develop HLA antibodies in the plasma, which could contribute to a serious transfusion reaction in recipients called TRALI (Transfusion Associated Acute Lung Injury). Fountain Bio tests previously pregnant donors for HLA antibodies before accepting them as platelet donors.
Can I donate platelets if I take medication for a chronic condition?
Usually yes. Most prescription and over-the-counter medications do not affect platelet donation, and well-managed conditions like high blood pressure, diabetes, and high cholesterol generally do not disqualify you. What matters specifically is whether a drug interferes with how platelets function.
Lifestyle and Eligibility
Can I donate if I have a tattoo?
A tattoo applied at a state-licensed facility in the United States is acceptable immediately. A three-month wait applies only if the tattoo was done outside the United States, at a facility that is not state-licensed, or in a state that does not license tattoo facilities.
What about ear or body piercings?
Piercings are acceptable with no wait provided the procedure was sterile and the equipment was single-use. If the equipment was reused, or you are not certain it was sterile and single-use, a three-month wait applies.
Can I donate if I take PrEP or PEP?
Not right away. Pre-exposure prophylaxis (PrEP) and post-exposure prophylaxis (PEP), and any other medication taken to prevent HIV infection, carry a three-month wait from your last dose.
Why, if these medications prevent HIV?
Because of what they do to the test results rather than anything they do to you. These medications can suppress HIV to a level that donor screening tests cannot detect in a donated unit. If someone acquired HIV while taking them, the infection could be missed and the unit released. The deferral is a limitation of the testing, not a judgment about your health or your risk.
Should I stop taking PrEP so I can donate?
No. Never stop a medication prescribed for you in order to become eligible to donate.
Do you still defer men who have sex with men?
No. That policy ended on December 6, 2023, when the FDA's individual donor assessment took effect. Men who identify as gay or bisexual are no longer asked whether they have had sexual contact with another man, and sexual orientation and gender identity no longer factor into eligibility. Screening now looks at individual, recent activity, applying the same standard to everyone.
Aspirin and Other Medications
Why does aspirin matter for platelets but not for whole blood?
Aspirin permanently disables the platelets that are in your bloodstream when you take it. An affected platelet stays impaired for the rest of its 7-to-10-day life. Waiting a couple of days gives your body time to produce enough new, unaffected platelets so that the collected unit works properly in a patient.
How long do I need to be off aspirin?
At Fountain Bio, we require that a donor not take aspirin for two full calendar days prior to donation. This means the two days before your appointment must be aspirin-free. This restriction also includes combination products that contain aspirin.
What about other blood thinners and antiplatelet drugs?
Comparison of platelet, whole blood, and double red cell donations
Medication ClassGeneric NameBrand NameRequired Waiting Period
Antiplatelet agentspiroxicamFeldene2 Days
—prasugrelEffient3 Days
—ticagrelorBrilinta7 Days
—clopidogrel / ticlopidinePlavix / Ticlid14 Days
—vorapaxarZontivity1 Month
Anticoagulantsfondaparinux, apixaban, dalteparin, enoxaparin, dabigatran, edoxaban, rivaroxabanArixtra, Eliquis, Fragmin, Lovenox, Pradaxa, Savaysa, Xarelto2 Days
—warfarinCoumadin, Warfilone, Jantoven7 Days
Can I take ibuprofen or other anti-inflammatories?
Yes. Ibuprofen and naproxen have reversible effects on platelets and clear quickly. Acetaminophen has no effect on platelet function and is the safest choice for pain relief prior to donating.
I take daily aspirin on my doctor's orders. What should I do?
Do not stop it. Never interrupt a medication prescribed by your physician in order to qualify as a donor. Inform the staff about what you take and why it was prescribed.
How Often You Can Give
Getting Ready
What the Procedure Is Like
How does apheresis work?
Blood is drawn through sterile single-use tubing into a machine that spins it to separate components by density. Platelets are diverted to a collection bag, while red cells, white cells, and most plasma are returned to you. No more than about 15% of your total blood volume is outside your body at any moment.
Will they use one arm or two?
Fountain Bio uses a single-needle procedure that alternates between drawing and returning through the same vein, leaving your other arm free.
What is a single, double, or triple donation?
A single is one full adult dose. If the machine collects enough for two or three separate transfusable doses, that is a double or triple. Yield is predicted based on your complete blood count results and total blood volume.
Does it hurt?
There is a brief pinch when the needle enters, but most donors feel no discomfort for the rest of the session.
What is citrate, and why is it used?
Citrate is an anticoagulant mixed into the blood outside your body to prevent clotting in the machine. It works by temporarily binding calcium. As it returns to your body, it temporarily lowers free calcium, which can cause mild tingling, a metallic taste, or lightheadedness. Your body clears citrate quickly after the procedure.
Tingling, Chills, and Staying Comfortable
What does a citrate reaction feel like?
Symptoms often start as tingling/numbness around the lips or fingertips, a metallic taste, faint vibrations, chills, or lightheadedness.
How common is it?
It occurs in roughly 7% of apheresis procedures. The overwhelming majority are mild and resolve quickly with minor adjustments.
What will staff do about it?
They can offer chewable calcium antacids (like Tums), slow the machine's flow rate, or provide warm blankets. If symptoms persist, they will pause or stop the procedure.
When should I say something?
Notify staff at the first hint of symptoms. Early detection allows quick resolution with a simple antacid or flow adjustment.
What if I feel faint?
Tell staff immediately. They will recline your seat, elevate your legs, apply a cool cloth, and provide fluids.
After You Donate
What Happens to Your Platelets

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