Know the risks

Illustration of a woman holding a red tick for donating blood
You're in good hands

At Lifeblood, your safety is our priority. We’ve pulled out all the stops to make sure donating blood and plasma is a really safe process.

We have expert team members at your side  to make your experience as safe and comfortable as possible. 

We also have restrictions on how often you can donate: every two weeks for plasma, and every twelve weeks for blood.

Most people feel fine during and after their donation. You might feel a small sting when the needle goes in, but you shouldn’t feel any discomfort during the donation.

That said, as with any procedure, reactions can sometimes occur when donating blood or plasma – before, during or after you leave the donor centre.

As you get set to donate, rest assured that most reactions are minor and go away quickly. The most common reactions are bruising and feeling faint. For women aged 18–45, check out our advice on iron health and blood donation

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Information to help you decide

We want you to know the possible reactions and chances they might happen, so that you can make decisions that are right for you.

Reactions from donating blood and plasma can relate to needle placement or movement, the loss of blood volume, or just being anxious. Less commonly a reaction can be related to an allergy or sensitivity to the materials or solutions that are used, or a technical issue with the machines used to collect plasma and platelets.

The loss of iron and haemoglobin may also cause some donors to develop symptoms; for more details please check out our advice on iron health and blood donation.

Make sure you follow the instructions we give you to make your experience as safe as possible whenever you make the incredibly generous decision to donate blood and ultimately save lives.​​​​​​ 

If you experience a reaction or feel unwell, it’s important to tell the staff so our expert team can ensure your comfort and safety. If you are feeling unwell after donating, call 13 14 95 and our team can give you advice.

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Will I have a reaction if I donate blood?


The likelihood will depend on your sex, age, and whether you are donating blood, plasma or platelets.


In general, the risk is higher if you're younger, haven't donated blood before or are fairly new to donating, and/or female.


Plasma and platelet donations generally have higher likelihood because it takes longer as we return your red cells and for plasma, infuse saline to help replace the fluid you have lost.

Chances of having a reaction

Let's break down the odds of having a reaction.

If you are after more information on these, keep scrolling down to read more!

Very common

(More than 1 in 10)

  • Minor bruising 


(1 in 10 to 1 in 100)

  • Feeling faint1


(1 in 100 to 1 in 1,000)

  • Large bruise
  • Fainting1
  • Nerve irritation
  • Painful arm
  • Swelling or pain in arm from fluid leaking into tissues2
  • Mild citrate reaction2


(1 in 1,000 to 1 in 10,000)

  • Delayed bleeding
  • Localised allergic reaction
  • Any event requiring outside medical care
  • Moderate citrate reaction2

Very rare

(1 in 10,000 to 1 in 100,000)

  • Piercing of an artery
  • Local inflammation of the vein 
  • Chest pain3

(1 in 100,000 to 1 in 1,000,000)

  • Cellulitis (skin infection)
  • Nerve injury causing prolonged period of pain or weakness
  • Clot in the deep veins of arm (uncommonly, the clot may travel to the lungs which may rarely cause significant symptoms)
  • Symptoms from return of damaged red cells2
  • Severe citrate reaction2

(Less than 1 in 1 million)

  • Major allergic reaction (anaphylaxis)
  • Major blood vessel or tendon injury 
  • Symptoms from return of clotted blood2
  • Symptoms from air entering the vein2

1 Younger donors, females and new donors have a higher likelihood of feeling faint. For example, a new female donor has a likelihood of around 1/10 compared to an experienced female donor who has a likelihood of 1/50
2 These occur only in plasma and platelet collections
3 Chest pain is often coincidental or related to another reaction such as anxiety

Some medical events may occur following a blood donation such as a heart attack or stroke. They are almost always determined to be unrelated to blood donation. 
The rates provided were last updated in March 2022 and are usually based on our own experience. Some events are extremely rare and so for those we may need to consider information from other blood services that are published in the literature.

Reaction symptoms

Feeling faint or fainting

Feeling faint may include feeling dizzy, light-headed, hot, sweaty, and/or nauseous. It can happen during donation, straight after donating or after leaving the donor centre. Only a small proportion of donors actually faint which can cause an injury.

See our tips to help with feeling faint



Small bruises will generally resolve in a few days. Occasionally larger bruises can develop and be uncomfortable for several days and take several weeks to resolve.

See our tips to help with bruising


Plasma and platelets risks

When you donate plasma and platelets, citrate is added to stop the blood clotting as we collect it, and a small amount is returned to you with your red cells.

You might experience a mild sensitivity to the citrate because of its effects on calcium and magnesium, which can include chills, tingling of the lips or tongue, or a metallic taste. Moderate symptoms are uncommon and include tingling of hands or feet, shivering and muscle twitching.

The following are very rare events. A life-threatening reaction can occur but the likelihood of an event occurring is minimised by our safety protocols:

  • Severe reaction to citrate: can include muscle contractions or spasms, seizures, breathing difficulties or disturbance of heart rhythm.
  • Damage to red cells in the machine: if returned to you in a large volume, it can cause blood in the urine, fevers and back pain. If you are healthy, there are no long-term side-effects from return of damaged red cells.
  • Disruption to the delivery of citrate causing clotting in the tubing: if returned to you, this may cause blocking of a blood vessel. Symptoms can include dizziness, breathlessness, coughing, chest pain or limb swelling.
  • Entry of air into the collection line: if returned to you (air embolus), can cause blockage to blood vessels resulting in symptoms such as breathlessness or chest pain.

Are there risks to being a frequent platelet donor?

The amount of citrate returned to you during a platelet donation is higher than returned for a donation where just plasma is collected. Citrate causes a temporary drop in calcium, but studies have not consistently shown any long-term bone health effects in frequent platelet donors.

Some studies have shown a reduction in a specific type of white cell (lymphocyte) in some frequent platelet donors. Further research is underway, but to date there is no confirmed evidence of long term consequences for health.


Other needle-related reactions explained

Nerve irritation Transient shooting arm pain or pins and needles in the arm or hand
Localised allergic reaction Redness and swelling near needle site
Piercing of an artery If the needle goes into an artery instead of a vein, the flow is under high pressure and there is a much higher likelihood of bruising if any blood leaks into surrounding tissues
Local inflammation of the vein Tenderness and redness in the area of the vein usually occurring several days after donation
Cellulitis Infection of the skin usually causing redness, swelling, pain and warmth in the area affected, which generally occurs 1-2 days after donation
Nerve injury Damage to nerves can lead to pain, pins and needles and occasionally weakness in the arm
Major blood vessel or tendon injury Injury which may cause prolonged discomfort or impaired function and/or may require surgery to correct


Allergic reactions

A localised reaction (e.g. redness, swelling, itching) can occur as a result of an allergy to materials or solutions used when you donate blood.

Very rarely, severe allergic reactions can occur causing symptoms such as, breathlessness, wheezing, facial swelling, difficulty swallowing, and/or swollen tongue. This can be life-threatening and requires emergency treatment.

Answering your questions

When I give plasma, my blood goes through plastic tubing and back to me. Is that safe?

We use a new sterile needle and kit that is used once and discarded, so it's all brand new for your donation.

The plasma and platelets kits contain Di-(2-ethylhexyl) phthalate (DEHP), which is a plasticiser used in many medical devices and procedures. It's been used in medical procedures for more than 40 years with no reports of negative side effects.

In fact, no toxic effects have been seen in humans. However, animal studies with very high doses of DEHP have shown development and reproduction issues.

Phthalates including DEHP are in a lot of things we come into contact with every day, including food, air, water, containers, flooring, and more. So, you may be exposed to small amounts of DEHP when you donate plasma or platelets, but it’s less than you’re normally in contact with day to day. We make sure vulnerable groups (like pregnant women) don’t donate, and our processes are designed to minimise your exposure.

We know some people have concerns, so we’re keeping a close eye on research into alternatives. For now, though, DEHP is necessary to improve the strength, consistency and effectiveness of the equipment used to collect and hold blood.

I am on an International Visa am I able to donate?

Yes, donors on Visas are welcome to donate, however we recommend you ensure you have the relevant Health Insurance, according to your class of visa, when donating blood. This requirement is for the safety of donors who may, rarely, require medical treatment due to an adverse event when donating blood. If you do not have the relevant Health Insurance, you may be responsible for payment of the treatment costs in the event of an adverse event.

Want advice to prepare, or for aftercare?

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