Answer the side-effect intent for pfizer vaccine without diagnosing; distinguish common from serious reactions and give safe next-step/reporting guidance.
Part of vaccines & immunisation side effects.
Sources
This page covers the Pfizer COVID-19 vaccine — a group of products, not a single one. Each statement below is taken from the SAHPRA-approved patient information leaflet named beside it:
- COMIRNATY READY TO USE ADULT VACCINE (Tozinameran, approved 15/11/2022)
Retrieved 2026-09-03. Your own medicine’s leaflet is the one that applies to you, and where it differs from this page the leaflet is correct.
What is Pfizer vaccine?
The Pfizer COVID-19 vaccine — one product is registered for this in South Africa, and this page is built from its approved leaflet.
The product and its leaflet:
- Tozinameran — COMIRNATY READY TO USE ADULT VACCINE, Pfizer Laboratories (Pty) Ltd (Dispersion for injection)
Check your own pack
The leaflet inside your pack is the one that applies to you.
Common side effects of Pfizer vaccine
Each medicine in this group has its own approved leaflet, and the effects below are the ones that leaflet lists. They are shown separately rather than combined, because the leaflets do not agree on what to list or how to word it.
Tozinameran (COMIRNATY READY TO USE ADULT VACCINE)
- headache
- nausea
- joint pain
- muscle pain
- injection site pain
- tiredness
- chills
- fever
- injection site swelling
- injection site redness
- enlarged lymph nodes (more frequently observed after the booster dose)
- allergic reactions such as rash or itching, hives or swelling of the face
The leaflet lists 10 more. Read the full leaflet.
Serious side effects and warning signs
None of the leaflets reviewed set out a separate serious-effects list.
General warning signs that apply to any medicine
Call for emergency help now if any of these happen
- Difficulty breathing, wheezing, or tightness in the throat or chest
- Swelling of the face, lips, tongue or throat
- A widespread rash with blistering or peeling skin, or sores in the mouth, eyes or genitals
- Fainting, collapse, or a sudden severe drop in alertness
- Chest pain, or sudden weakness or numbness on one side of the body
- A fit (seizure), or confusion that comes on suddenly
In South Africa call 10177 for an ambulance, or 112 from a mobile phone. Go to your nearest emergency department if it is faster. Do not wait to see whether the symptom settles.
How long can side effects last?
How long a side effect lasts depends on the effect, the product, how long it has been used, and the person. Some effects ease within days as the body adjusts. Others continue for as long as the product is used. A few can persist after stopping, and some need review rather than waiting.
- Settling effects — mild effects that ease over the first days or weeks of use
- Ongoing effects — effects that continue while the product is being used and improve after stopping
- Persistent effects — effects that continue after stopping and need medical review
- Delayed effects — effects that appear after weeks or months rather than immediately
Which of these applies to a particular effect is a clinical question. If a side effect is not settling, is getting worse, or is affecting your daily life, that is worth a conversation with a pharmacist or doctor regardless of how long it has been going on.
Evidence required before publish — source the following for Pfizer vaccine from the SAHPRA-approved patient information leaflet or professional information, and cite what you actually used.
- Anything the approved information for Pfizer vaccine says about how long specific effects last
- Whether the source describes any effect as usually temporary, or as needing review if it persists
- Whether any effect is described as continuing after the product is stopped
Factors that may affect side effects
Cautions from each medicine’s approved leaflet.
Tozinameran (COMIRNATY READY TO USE ADULT VACCINE)
Do not use it at all if:
- if you are hypersensitive (allergic) to COVID-19 mRNA vaccine (nucleoside modified) or any of the other ingredients of COMIRNATY READY TO USE ADULT VACCINE (listed in section 6)
Use with care, and tell your doctor, if:
- if you have ever had a severe allergic reaction or breathing problems after any other vaccine injection or after you were given COMIRNATY READY TO USE ADULT VACCINE in the past
- if you are feeling nervous about the vaccination process or have ever fainted following any needle injection
- if you have a severe illness or infection with high fever. However, you can have your vaccination if you have a mild fever or upper airway infection like a cold
- if you have a bleeding problem, you bruise easily or you use a medicine to prevent blood-clots
- if you have a weakened immune system, because of a disease such as HIV infection or a medicine such as corticosteroid that affects your immune system There is an increased risk of myocarditis (inflammation of the heart muscle) and pericarditis (inflammation of the lining outside the heart) after vaccination with COMIRNATY READY TO USE ADULT VACCINE. These conditions can develop within just a few days after vaccination and have primarily occurred within 14 days. They have been observed more often after the second vaccination, and more often in younger males. Following vaccination, you should be alert to signs of myocarditis and pericarditis, such as breathlessness, palpitations and chest pain, and seek immediate medical attention should these occur. COMIRNATY READY TO USE ADULT VACCINE may not fully protect all those who receive it and it is not known how long you will be protected. You may receive a third dose of COMIRNATY READY TO USE ADULT VACCINE. The efficacy of COMIRNATY READY TO USE ADULT VACCINE, even after a third dose, may be lower in people who are immunocompromised. In these cases, you should continue to maintain physical precautions to help prevent COVID-19. In addition, your close contacts should be vaccinated as appropriate. Discuss appropriate individual recommendations with your health care provider. Due the evolution of SARS CoV2 variants in South Africa, vaccinated patients are advised to report any COVID or suspected COVID to their doctor to enable collection of virus samples for analysis. Children COMIRNATY READY TO USE ADULT VACCINE 30 micrograms/dose dispersion for injection is not recommended for children aged under 12 years. There is a paediatric presentation available for children 5 to 11 years of age. For details, please refer to the concentrate for dispersion for injection
What to do if you experience side effects
If you think you are having a side effect, the response depends on how severe it is. Use the warning signs above first — if any of those apply, treat it as urgent.
If the symptom is severe or frightening
Get medical help immediately. Call 10177 for an ambulance, or 112 from a mobile phone, or go to the nearest emergency department. Take the product and its packaging with you if you can.
If the symptom is mild but bothering you
- Write down what the symptom is, when it started, and how it relates to when you take the product
- Check the leaflet that came with the product to see whether the symptom is listed
- Speak to your pharmacist — for many questions this is the fastest route to a useful answer
- Contact the prescriber if the symptom is affecting your daily life or is not settling
Do not stop a prescribed treatment on your own
Stopping some treatments suddenly causes its own problems, and the condition being treated may get worse. If you want to stop, ask a pharmacist or doctor how to do it safely — they can usually offer an alternative.
You can also report a suspected side effect in South Africa. Reporting does not replace getting medical advice, and you do not need to be certain the product was the cause.
When to seek urgent medical help
Some symptoms need medical attention straight away rather than an appointment in a few days. Do not wait to see whether they settle.
Call for emergency help now if any of these happen
- Difficulty breathing, wheezing, or tightness in the throat or chest
- Swelling of the face, lips, tongue or throat
- A widespread rash with blistering or peeling skin, or sores in the mouth, eyes or genitals
- Fainting, collapse, or a sudden severe drop in alertness
- Chest pain, or sudden weakness or numbness on one side of the body
- A fit (seizure), or confusion that comes on suddenly
In South Africa call 10177 for an ambulance, or 112 from a mobile phone. Go to your nearest emergency department if it is faster. Do not wait to see whether the symptom settles.
Get same-day medical advice if you have
- A high fever, or a rash together with feeling generally unwell
- Yellowing of the eyes or skin, or unusually dark urine
- Unusual bruising or bleeding that you cannot explain
- Severe or persistent vomiting or diarrhoea, especially if you cannot keep fluids down
- A sudden change in mood, or thoughts of harming yourself
- Any symptom that is rapidly getting worse
If you are having thoughts of harming yourself
Help is available in South Africa. The SADAG helpline is 0800 567 567, or you can go to your nearest emergency department. You do not have to wait until it feels like an emergency.
How to report a suspected side effect in South Africa
South Africa has an official system for reporting suspected side effects, run by the South African Health Products Regulatory Authority (SAHPRA). Reports from the public and from healthcare professionals are how safety signals get detected after a product is already in use.
Who can report
Anyone can report — you do not have to be a healthcare professional, and you do not need to prove that the product caused the problem. A suspicion is enough. Patients, caregivers and family members can all submit a report.
What to have ready
- The name of the product, its strength and form, and the batch number if you have it
- Why it was being used, and when it was started and stopped
- What the suspected reaction was, when it began, and how long it lasted
- Any other medicines, supplements or remedies being used at the same time
- Basic details about the person affected — age and sex are usually enough
How to report
SAHPRA accepts adverse reaction reports through its e-Services reporting system and through the Med Safety mobile app. Healthcare professionals can also report through the same routes. Current forms and access points are published on the SAHPRA site.
- SAHPRA Health Products Vigilance — the main vigilance and reporting hub
- SAHPRA e-Services — current adverse reaction reporting access
Reporting is not a substitute for medical care
If someone is unwell now, get medical help first and report afterwards. Urgent symptoms always take precedence over paperwork.
For a fuller walkthrough see how to report an adverse drug reaction.
Related pages
← Back to more medicine side effects.
Report a side effect
If you think you have had a side effect, you can report a suspected side effect in South Africa. Report a suspected side effect through the appropriate SAHPRA pathway where relevant.
Information only
This page gives general medicine-safety information for people in South Africa. It is not a diagnosis and not personalised medical advice. It cannot tell you whether a symptom you are having is caused by a particular product. Speak to a pharmacist or doctor about your own situation, and do not stop or change a prescribed treatment on the basis of a web page.
Editorial status: draft — not for publication
Brief SE-00280 · build rank 280 · Phase 2 · Tier 2. Every evidence slot on this page must be completed from the SAHPRA-approved source and the page signed off by a qualified clinical or pharmacy reviewer before it is published. Target length 1,300–2,000 words.