Pneumovax 23 also known as Pneumococcal Vaccine Polyvalent is a vaccine that was created in order to protect against several types of infections:
- ear infection
- nasal infection
- diseases like pneumonia
- blood infection (medically known as bacteremia)
- meningitis, which affects the covering membranes of the brain through the action of a bacteria called Streptococcus Pneumoniae
This vaccine is necessary for the prevention of infections in individuals in the vulnerable category (children, the elderly, and people with underlying health issues). People that are considered at risk o are those with diseases that affect organs like the heart, liver, kidneys, the immune system, lungs, and blood.
According to scientific researchers, Pneumovax 23 also benefits people aged over 65+ as well as cancer patients.This vaccine is also used as a secondary treatment against cancer as it contains a compound that interacts simultaneously alongside steroids to kill cancer cells. It is implemented together with chemotherapy and radiation in patients with cancer.
There are however, side effects as in many other vaccines:
- Injection site reactions like pain, redness, rashes and hard lumps
- Chills
- Headache
- Nausea
- Vomiting episodes
- Fatigue
There are other symptoms linked to the vaccine like fainting or dizziness, seizure, numbness, and blurred vision. These are not dangerous signs of side effects but you should let your doctor know about them.
Only a small number people react to this vaccine, the vast majority won’t even feel any side effects.
How to deal with vaccine side effects
- Pain: you should consult your doctor before taking any painkiller. Don’t take acetaminophen.
- In case of vomiting and nausea, go to your healthcare provider or to the pharmacist as soon as possible.
- Some of the worst side effects of Pneumovax 23 are numbness of feet and hands, bleeding, and swollen glands. In event of having those symptoms, don’t hesitate to make your healthcare provider a phone call.
If you have your doubts about the side effects of this vaccine, you should ask your doctor about it or research on the Internet, as there are lots of institutions and healthcare centers that have provided enough information related to the topic on their websites.
How is the vaccine administered?
A syringe containing 0.5 ml of vaccine is used to inject under the skin.
Some healthcare practitioners might inject it intramuscularly. When it is injected in the muscle, the area chosen for the injection is either in the shoulders or thighs.
Clinical trials experience
Vaccine laboratories conduct clinical trials before releasing any newly developed vaccine on the pharmaceutical market.
Clinical trial results are totally different from the ones seen in practice or real life. And this vaccine has been tested in many ways:
People aged 50-64 and older were divided into four different cohorts.
The clinical trial was:
- Randomized
- Double-blind
- Placebo-controlled
The volunteers received two types of injections: no pneumococcal vaccination and pneumococcal polysaccharide.
Subjects were randomly chosen to be administered intramuscular injections with a placebo that contained saline and phenol every 7 days in a month.
The study evaluated three factors: first vaccination, revaccination, and reactions according to ethnicity.
The results were based on the reactions experienced in a sample of more than 550 individuals from all across the world.
Results
In this study, of 550 individuals, only 10 people reacted inappropriately to the vaccination.
Some of the reactions observed in these individuals within the 14 days of vaccination were :
- Angina pectoris
- Chest pain
- Headache
- Stiffness
- Urinary retention

The other 5 subjects had other types of reactions after 20 days of the first vaccination. This time, they received 3 injections of the vaccine plus two placebos. Cerebrovascular accident pancreatitis, myocardial infarction, and death were some of the reactions after 20 days of clinical experimentation. 4 people died during the trials.
According to these results, the major part of these reactions occurred after the first injection. The most common side effects were pain, tenderness, soreness, and erythema. Headaches and asthenia were reported as the most common systemic adverse experiences.
As for the reactions following revaccination, subjects felt pain, tenderness, swelling, fatigue, and myalgia. These symptoms were much less severe than the ones experienced after the initial vaccination.
What happened to people over 65? The worst reactions came just after revaccination. The percentage of subjects who experienced discomfort with the vaccination site was much higher than the one observed in their peers younger than 60. People this age experienced certain reactions, some of which were fatigue and myalgia.
It is important to remark that the use of analgesics was more noticeable in people younger than 60 than in the other cohort or group of older individuals. For the most part, they resort to painkillers after the initial vaccination, while only 4% of them utilized analgesics after revaccination.
The trial conclusion, resulted with this list of the symptoms that may be caused by the vaccine, separated by the body systems and organs.
- General disorders: fever, decreased limb mobility.
- Digestive system: vomiting and nausea.
- Lymphatic system; Leukocytosis and hemolytic anemia in special cases.
- Hypersensitivity: serum sickness and angioneurotic edema.
- Musculoskeletal system: arthritis.
- Nervous system: radiculoneuropathy and febrile convulsion.
- Skin: rash and cellulitis.
- Others: increased serum C – reactive protein.