Clinical safety
Use your own team’s instructions first
Use the contact number and urgent-care advice your team gave you for new or worsening symptoms. If you are having systemic anti-cancer treatment, use the 24-hour number on your treatment alert card. Call 999 for a life-threatening emergency.
Link blood-count effects to symptoms and safety
A blood result is interpreted alongside symptoms, treatment and trends. Do not use somebody else’s transfusion or treatment threshold.
What to record between blood tests
This helps the team distinguish tiredness from a more urgent change.
- Breathlessness, dizziness, palpitations, chest symptoms, headache and how far you can walk or climb.
- New bruises, pinpoint spots, nose or gum bleeding and bleeding that takes longer to stop.
- Blood in vomit, urine or stool, black stool or unusually heavy vaginal bleeding.
- Falls, fainting, infection symptoms and medicines that may affect bleeding.
- The dates and results the team chooses to share, without comparing them to a generic internet range.
- Who to call before dental work, an operation or starting any bought medicine.
Questions after a changed blood count
Ask about the cause, expected course and action rather than one isolated number.
- Is treatment, bleeding, nutrition, kidney function or another cause being considered?
- Does this result require repeat testing, treatment delay or supportive treatment?
- Which symptoms mean I should call before the next blood test?
- Should any prescribed medicine be reviewed by the prescriber?
- Is iron, B12, folate or another treatment appropriate only after a deficiency is confirmed?
Report bleeding with context
Include treatment and medicines if known.
“I am on cancer treatment and have new bleeding that has not stopped with the first-aid advice I was given. I also feel faint and need urgent assessment.”
Separate red-cell symptoms from platelet and bleeding problems
Cancer and its treatment can lower red cells, platelets or both. Anaemia often affects oxygen-carrying capacity, while low platelets or clotting problems can increase bleeding, and each needs assessment in its clinical context.
Anaemia may cause fatigue, breathlessness, dizziness, palpitations, headache or reduced exercise tolerance. These symptoms also have other causes, so a blood test and clinical review matter. Treatment might address bleeding, nutrition, marrow suppression or another cause and can sometimes include transfusion. Do not start iron, folate or vitamin B12 simply because haemoglobin is low; supplementation helps only when the relevant deficiency exists and is safe to treat.
Low platelets can lead to easy bruising, pinpoint red or purple spots, nosebleeds, gum bleeding or prolonged bleeding from small cuts. Cancer medicines can also affect clotting or interact with aspirin, ibuprofen, anticoagulants, herbal products and alcohol. Give the oncology team a complete list. Do not stop a prescribed blood thinner or take extra pain relief without individual advice.
Reduce injury without becoming immobile. Use a soft toothbrush if advised, an electric razor, gloves for sharp tasks and well-fitting footwear. Avoid contact sports and activities with a high fall risk while counts are low. Ask what dental work, injections, rectal medicines and invasive procedures require prior approval. Keep the unit's exact thresholds and transfusion plan, since one number does not fit every person.
A practical way through it
Use the parts that fit your situation and leave the rest.
- Distinguish the symptom patternRecord breathlessness, dizziness and palpitations separately from bruises, pinpoint spots, nosebleeds, gum bleeding, blood in urine or stool and heavy vaginal bleeding.
- Check medicines and supplementsShow clinicians all prescriptions, occasional painkillers, herbs and vitamins, including products that may affect platelets, the stomach or anticoagulation.
- Prevent avoidable injuryUse safer grooming and household tools, protect hands and feet and postpone high-risk activity according to the clinical team's count and treatment advice.
- Manage a minor nosebleed correctlyUse the first-aid method your team provides and contact them if bleeding persists or meets their urgent threshold rather than repeatedly checking or packing the nose.
- Plan procedures in advanceTell dentists and other clinicians about cancer treatment and recent blood results, and coordinate invasive care with the oncology or haematology team.
- Escalate functional declineCall about rapidly increasing breathlessness, faintness, reduced ability to walk, persistent bleeding or many new bruises rather than waiting for routine bloods.
What this can look like
When bruises appear before a dental visit
Mina notices several unexplained bruises and gum bleeding on the morning of a planned tooth extraction during chemotherapy.
A useful response
Contact the cancer team and dentist before the procedure and report the new bleeding signs.
Ask whether current blood counts and medicine timing make the extraction safe or whether it should be rearranged.
Do not stop prescribed anticoagulants or take anti-inflammatory painkillers without specific advice.
What blood counts mean
- Low haemoglobin may cause dizziness, palpitations and breathlessness.
- Low platelets may cause nosebleeds, bleeding gums or pinpoint skin spots.
Reducing avoidable harm
- Check before taking aspirin, ibuprofen or supplements that may affect bleeding.
- Do not start iron unless a clinician confirms iron deficiency and recommends it.
Contacting the team
- Use the treatment team promptly for new bruising or bleeding, blood in urine or stool, or sudden breathlessness.
- Call 999 for uncontrolled or heavy bleeding, vomiting blood with faintness or rapid deterioration, or sudden facial weakness, one-sided weakness or speech change.
A manageable next step
What you could do now
- Keep scheduled blood tests.
- Review over-the-counter medicines with your team.
- Use the treatment number for new bleeding or marked breathlessness.
Checked sources
Read the original guidance
We summarise carefully and link to the source so you can check the full, most current information. Sources were checked 9 September 2026.