Covishield Vaccine - Dosage and Side effects

Covishield Vaccine - Dosage and Side effects

ChAdOx1 nCoV or Covishield is a recombinant vaccine against the COVID-19 virus developed by Oxford University and AstraZeneca and manufactured by the Serum Institute of India Pvt. Ltd, on 15 February 2021. The product consists of genetically modified organisms (GMO'S) that is replication-deficient chimpanzee adenovirus with SARS-COV- 2 spike protein gene incorporated and produces S-antigen protein that is specific to SARS-COV-2 to generate immunity against COVID-19 virus. WHO approved the vaccine for emergency use during the pandemic.

What Patient has to mention to the Health care professional before vaccine administration

1. If the patients want to administer vaccine they should mention the following details to the doctor

2. If the patient is having an allergic reaction due to food, drug, vaccine, or any ingredient of the vaccine.

3. If the patient is suffering from fever.

4. If the patient is having any bleeding disorder like hemophilia or is on any anti-coagulant or blood thinner therapy.

5. If the patient is immunocompromised and receiving any type of medication that affects the immune system example immunosuppressants in organ transplantation.

6. Pregnant females.

7. Breastfeeding females.

8. If a patient received any other COVID-19 vaccine.

Read also- Live Covid 19 Status in india

Side effects of the vaccine

First dose 

1. Very Common 

b. Tenderness, pain, warmth, redness, itching, swelling, or bruising at

c. Generally feeling unwell at the site of injection.

d. Fatigue

e. Chills and fever

f. Headache

g. Nausea

h. Joint pain or muscle ache


2. Common Side Effects 

a. A lump at the site of injection

b. Fever

c. Vomiting

d. Flu-like symptoms, such as high temperature, sore throat, runny nose, cough and chills


3. Uncommon 

a. Dizziness

b. Loss of appetite

c. Pain in abdomen

d. Enlarged Lymph nodes

e. Excessive sweating, itchy skin, or rashes


Second dose 

The intensity of the side effects increases after second dose

1. Very Common: The severity of the following symptoms increases after second dose

i. Tenderness, pain, warmth, redness, itching, swelling, or bruising at

j. Generally feeling unwell at the site of injection.

k. Fatigue

l. Chills and fever

m. Headache

n. Nausea

o. Joint pain or muscle ache


2. Common 

e. A lump at the site of injection

f. Fever

g. Vomiting

h. Flu-like symptoms, such as high temperature, sore throat, runny nose, cough and chills




Special warnings and Precautions


1.    Elderly population

The safety and efficacy of the vaccine are studied in the population >= 65 years of age and no adjustment of the dose is required in such elder patients.

2. Pediatric population

The safety and efficacy data on the patients of age group <=18 years is not studied and established yet so the vaccination of the pediatric population should be avoided to prevent any kind of adverse effect or event.

3. Hypersensitivity reaction

Patients receiving the vaccine should be monitored as the patient can suffer from any type of allergic or anaphylactic reaction due to any ingredient of the vaccine after administration.

4. Concurrent illness

The vaccination of the patients with acute severe febrile illness should not be done as it can worsen the condition of the patient that could also be fatal, but in case of minor infection like a cold or low-grade fever the vaccination should be done without any delay.

5. Thrombocytopenia and coagulation disorders

In patients with thrombocytopenia, any coagulation disorder, or who are on anticoagulant therapy the vaccine should be administered cautiously as it can lead to bleeding, bruising after the intramuscular administration.

6. Immunocompromised individuals

The patients who are immunocompromised or are on any immunosuppressant therapy as in the case of organ transplantation should avoid vaccination as the safety and efficacy of the patients are not studied and hence it is not known that the same response will occur in such patients as in immunocompetent individuals. Immunocompromised patients have a weak immune response to the vaccine and its regimen.

7. Pregnancy and Breastfeeding 

The safety and efficacy of the vaccine and its ingredient are not known yet on pregnant and breastfeeding females as it can be potentially fatal for the newborn or fetus so vaccination of such females should be avoided.

8. Concomitant vaccines

The effect of simultaneous use of Covishield with other vaccines is not studied in the population so the vaccine should not be administered with any other vaccine.

Efficacy of covishield vaccine

Covishield vaccine is proven to be 63.09% effective against symptomatic SARS-CoV-2 infection. It is also seen that the efficacy of larger dose intervals within 8 to 12 weeks is associated with greater efficacy.

How long does the covishield vaccine last?

The clinical trials on covishield proved that the vaccine can prevent the Covid-19 infection after administration of 2 doses between the time interval of 4-12 weeks. The duration of action of covishield is currently not known but it provides an immune response of 4 weeks after the second dose.

Effect of Covishield on SARS-COV-2 Variants

The SARS –COV-2 virus is continuously mutating due to spread and circulation in a large population around the world and hence the different types of variants keep on evolving in population. These variants may be having higher transmissibility, may cause severe disease, and can also be associated with re-infection and change in antigen composition. The studies showed that the Covishield vaccine may have a reduced effect on the B1.1.1.7 variant while there can be a decrease in effect in mild to moderate disease due to the B1.351 variant is going to be studied in the current clinical trials. Therefore the continuous monitoring of the vaccine effect on new variants needs to be studied due to alterations in DNA and genes of the virus.

Precautions while vaccine administration

1. Before, during, and after the vaccine administration patients are advised to follow the government guidelines for the COVID-29 protection like wearing masks, social distancing, and hand sanitization.

2. The vaccine should not be administered to the patient with COVID-19 signs and symptoms only patients who recovered or do not get infected can only be vaccinated.

3. Testing for COVID-19 should not be done for vaccine administration.

4. Healthcare workers should inform individual receiving vaccine about the possible side effects of the vaccine and their treatment, The patient should be monitored for 15 minutes after vaccination. 

5. The side effects of the vaccine should be treated with antipyretics and analgesics like paracetamol.

6. The individual receiving vaccine should complete the vaccination dose for better protection.