What’s actually slowing this PC down?
Pick the symptom - the matching free tool is one click away.
You may need to postpone a blood donation if you are unwell, have a low hemoglobin result, take certain medicines, recently traveled to an infection-risk area, or had a tattoo, piercing, pregnancy, birth, or other health event covered by your blood service’s rules. A delay is often temporary, but the exact decision depends on the organization collecting your blood and the details of your situation. Check with that service before your appointment; a general guide cannot confirm your individual eligibility.
Why blood services sometimes ask donors to wait
Eligibility screening is intended to protect both the person donating and the person who may receive the blood. The U.S. Food and Drug Administration (FDA) describes checks that can include general health, pulse, blood pressure, temperature, hemoglobin, infection risks, age under applicable law, and time since a previous donation. A blood service may ask about health and lifestyle at each appointment because circumstances can change between donations.
The same event does not necessarily lead to the same waiting period everywhere. The FDA overview concerns the United States, American Red Cross rules apply to that organization, and NHS Blood Donation guidance applies to its UK service. Their criteria and timelines should not be treated as interchangeable. Guidance can also be updated: the FDA’s blood-guidance index includes 2026 entries. Use the current rules of the organization that will collect your donation, rather than relying on an old appointment experience or a rule remembered from another country.
Common reasons you may be deferred
You feel ill or are recovering
If you do not feel well on donation day, the American Red Cross advises cancelling and returning after your symptoms have passed, in line with its guidance. Do not assume that a particular number of symptom-free days applies everywhere; other services may give different advice. If you are unsure whether symptoms have resolved enough, contact the collecting service before traveling to the appointment.
Free tools Windows power users keep installed
One-click scans. No signup required.
#1 Best Overall
- HD streaming made simple: With America’s number 1 TV streaming platform,* exploring popular apps—plus tons of free movies, shows, and live TV—is as easy as it is fun. *Based on hours streamed—Hypothesis Group
- Compact without compromises: The sleek design of Roku Streaming Stick won’t block neighboring HDMI ports, and it even powers from your TV alone, plugging into the back and staying out of sight. No wall outlet, no extra cords, no clutter.
- No more juggling remotes: Power up your TV, adjust the volume, and control your Roku device with one remote. Use your voice to quickly search, play entertainment, and more.
- Shows on the go: Take your TV to-go when traveling—without needing to log into someone else’s device.
- TV, simplified: With setup that only takes minutes, a simple-to-navigate Home Screen, and an uncluttered remote control that does all you need—Roku makes it easier to watch the TV you love.
Your hemoglobin or iron result is too low
A low hemoglobin screening result can mean you cannot donate that day. The Red Cross says a deferral for low iron does not necessarily prevent future donation. It is a reason to ask what to do next, not proof that you are permanently ineligible. Do not start a supplement or other treatment solely to try to pass a donation screening: the right response depends on your health, and the available guidance does not establish one treatment for every person.
You take medication or are being treated for a condition
Taking medication does not automatically disqualify you. The Red Cross says most medications do not prevent donation, but some require a wait after the final dose. The condition being treated can matter as well, so the medication name alone may not settle the question. Do not stop or skip prescribed medicine to donate. Instead, give the service the exact drug name, dose if requested, reason for taking it, and date of your last dose, and ask whether the medicine or the underlying condition affects timing.
Rank #2
- Ultra-speedy streaming: Roku Ultra is 30% faster than any other Roku player, delivering a lightning-fast interface and apps that launch in a snap.
- Cinematic streaming: This TV streaming device brings the movie theater to your living room with spectacular 4K, HDR10+, and Dolby Vision picture alongside immersive Dolby Atmos audio.
- The ultimate Roku remote: The rechargeable Roku Voice Remote Pro offers backlit buttons, hands-free voice controls, and a lost remote finder.
- No more fumbling in the dark: See what you’re pressing with backlit buttons.
- Say goodbye to batteries: Keep your remote powered for months on a single charge.
You recently traveled
Travel to a destination associated with malaria risk can affect eligibility. The destination and the date you returned may both matter. A country-level description is not enough to predict a decision, and the Red Cross examples include three-month waits for some travel criteria; that interval is specific to criteria used by that service, not a universal travel rule. Tell the service where you went and when you returned, and ask it to assess your itinerary against its current criteria.
You had a tattoo or body piercing
A recent tattoo or piercing may lead to a wait. The applicable rule can depend on local regulation and whether sterile, single-use equipment was used. The Red Cross describes three-month waits for some tattoo and piercing criteria, while NHS eligibility guidance describes waits of up to three months for certain listed circumstances. Those examples do not establish one rule for every procedure, location, or service. Be ready to explain when and where the procedure took place and, if you know, what equipment practices were used. Check the local service’s current rule rather than assuming a procedure is automatically allowed or automatically disqualifying.
Quick wins for a faster PC:
Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →Repair Windows errors before they cause bigger problemsFix Now →Scan for outdated or missing drivers - takes under a minuteDriver Scan →Rank #3
- 4K streaming made simple:With America’s number 1 TV streaming platform,* exploring popular apps—plus tons of free movies, shows, and live TV—is as easy as it is fun. *Based on hours streamed—Hypothesis Group
- 4K picture quality: With Roku Streaming Stick Plus, watch your favorites with brilliant 4K picture and vivid HDR color.
- Compact without compromises: Our sleek design won’t block neighboring HDMI ports, and it even powers from your TV alone, plugging into the back and staying out of sight. No wall outlet, no extra cords, no clutter.
- No more juggling remotes: Power up your TV, adjust the volume, and control your Roku device with one remote. Use your voice to quickly search, play entertainment, and more.
- Shows on the go: Take your TV to-go when traveling—without needing to log into someone else’s device.
You are pregnant or recently gave birth
NHS Blood Donation says a person cannot donate while pregnant and indicates a six-month wait after giving birth. These are NHS-specific rules, not a worldwide standard. If you are pregnant, recently gave birth, or have a related question about your circumstances, ask the collection organization that serves your location for its current guidance.
You have a sexual-health exposure, medical investigation, or other health history
Some sexual-health exposures and medical investigations can affect eligibility, as can other conditions or treatments. The relevant details and timing vary, and the general guidance summarized here does not provide a complete list or a universal waiting period. Answer the service’s health-history questions accurately and ask it directly about the specific exposure, test, investigation, or diagnosis. Do not infer a deferral period from a different condition or from another organization’s rules.
Rank #4
- Stunning 4K and Dolby Vision streaming made simple: With America’s number 1 TV streaming platform,* exploring popular apps—plus tons of free movies, shows, and live TV—is as easy as it is fun. *Based on hours streamed—Hypothesis Group
- Breathtaking picture quality: Stunningly sharp 4K picture brings out rich detail in your entertainment with four times the resolution of HD. Watch as colors pop off your screen and enjoy lifelike clarity with Dolby Vision and HDR10+.
- Seamless streaming for any room: With Roku Streaming Stick 4K, watch your favorite entertainment on any TV in the house, even in rooms farther from your router thanks to the long-range Wi-Fi receiver.
- Shows on the go: Take your TV to-go when traveling—without needing to log into someone else’s device.
- Compact without compromises: Our sleek design won’t block neighboring HDMI ports, so you can switch from streaming to gaming with ease. Plus, it’s designed to stay hidden behind your TV, keeping wires neatly out of sight
You donated recently
The FDA’s U.S. baseline eligibility overview says a donor must not have donated in the previous eight weeks. Treat that as an FDA-specific example, not a rule that applies to every donation type, service, or country. Tell the collection organization when and where you last donated so it can apply the appropriate interval.
How to check your eligibility before an appointment
- Identify the collecting service. Find the organization and location that will take your donation. Use its current eligibility information or contact channel; rules from the FDA, Red Cross, and NHS are not interchangeable.
- Write down the relevant dates. Note when symptoms began and ended, the last dose of any medication, the date of a procedure, travel and return dates, pregnancy or birth timing, and your most recent donation date. A service may need more than one date to assess your situation.
- Gather the details that distinguish one case from another. For travel, record destinations and itinerary. For a tattoo or piercing, note where it was done and what you know about sterile, single-use equipment. For medication or treatment, have the exact name and reason available. Share only what the service needs to make its assessment, but answer its eligibility questions honestly.
- Ask about the specific rule and the next eligible date. Instead of asking only whether you can donate in general, describe the event or treatment and ask whether it changes eligibility, whether the deferral is temporary, and when to check again. If the answer depends on further information, ask what information the service needs.
- Follow the service’s appointment advice. If you feel unwell, the Red Cross advises cancelling rather than donating that day. If a service tells you to wait, follow its timing and check again when that period has passed; another service’s interval may not apply.
What to expect during screening
Eligibility is assessed at the appointment, not guaranteed by a web page or a previous successful donation. The FDA overview describes checks such as health history, vital signs, hemoglobin, infection risks, and time since the last donation. NHS Blood Donation says it goes through a full health and lifestyle check at every appointment to help ensure donation is safe for the donor and patients. The collection organization may need to consider more than one factor, such as both a medicine and the condition it treats.
Best Value
- The Google TV Streamer (4K) delivers your favorite entertainment quickly, easily, and personalized to you[1,2]
- HDMI 2.1 cable required (sold separately)
- See movies and TV shows from all your services right from your home screen[2]; and find new things to watch with tailored recommendations for everyone in your home based on their interests and viewing habits
- Watch live TV and access over 800 free channels from Pluto TV, Tubi, and more[3]; if you find an interesting show or movie on your TV, mobile app, or Google search, you can easily add it to your watchlist, so it’s ready when you are[2]
- Up to 4K HDR with Dolby Vision delivers captivating, true-to-life detail[4]; and you can connect speakers that support Dolby Atmos for more immersive 3D sound
Be straightforward about recent changes and answer screening questions as accurately as you can. If a detail is uncertain, say so and ask how to clarify it rather than guessing. A decision to defer is not necessarily permanent; the Red Cross specifically notes that someone deferred for low iron may be able to donate in the future. Ask the service what applies to your case and whether there is a recommended time to contact it again.
How to interpret waiting periods and examples
Numbers are meaningful only when tied to the organization and circumstance that set them. For example, the FDA overview’s eight-week interval concerns its U.S. baseline guidance on time since a previous donation. The NHS’s six-month postpartum wait is an NHS rule. Red Cross materials describe three-month waits for some travel, tattoo, piercing, and other criteria; NHS guidance also describes up to three months for certain listed circumstances. These figures should not be combined into a single global timetable.
When an online page gives a waiting period, check whether it covers your exact circumstance, the relevant service, and the date the guidance was updated. A rule for one medication, destination, procedure, or exposure may not answer a different case. If the page is broad or your situation has more than one element, ask the collection organization rather than extending the stated period or shortening it on your own.
If you are deferred
- Ask what caused the deferral. Confirm whether the decision relates to a screening result, a health condition, a medicine, travel, a procedure, or another factor.
- Find out whether the decision is temporary. Ask whether you can return later and what event or date determines when to check again.
- Do not change medical treatment to qualify. Keep taking prescribed medication as directed and speak with your clinician about health concerns. Donation eligibility is not a reason to stop treatment or self-treat.
- Use the organization’s support channel for unresolved questions. The Red Cross directs donors with eligibility questions to its support channels; use the corresponding contact route for the service handling your appointment.
A blood service’s answer is the appropriate basis for deciding whether to book, keep, or reschedule an appointment. This explainer covers common reasons for waiting, not every diagnosis, medicine, destination, procedure, or national eligibility rule.
PC Slower Than It Used to Be?
A free scan shows the junk files, broken settings and background clutter dragging Windows down - then fixes them in one click.Free scan · Windows 10 & 11Crashes, No Sound, or Screen Glitches?
Random freezes, missing sound and display glitches usually trace back to one bad driver. Find and replace yours safely.Free scan · under a minuteQuick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
