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Woman in Italy Received 6 Doses of COVID-19 Vaccine At Once

Woman in Italy Received 6 Doses of COVID-19 Vaccine At Once

On May 9, Sunday, a 23-year-old woman in Tuscany, Italy, received six doses of the Pfizer-BionTech vaccine after the attending nurse mistakenly gave her doses equivalent to an entire vial. The vaccine in question requires only two doses, three weeks apart. Authorities are currently monitoring the woman for potential effects of COVID-19 vaccine overdose.

How it happened

The unnamed woman, a grad student who needed the shot for her clinical psychology program², said she immediately knew something was wrong after the vaccination: the nurse looked visibly distressed and promptly talked to the attending physician.

Dr. Tomasso Bellandi, director of patient security for the northwest Tuscany health authority, explained that a vial of the Pfizer vaccine contains six doses. Before administration, each dose is extracted and transferred to individual vials where they are diluted¹.

COVID-19 vaccine overdose

When the incident occurred, the nurse thought the vials were already diluted. Bellandi described both diluted and undiluted vaccines look transparent, with the same density. “This contributed to the error,” he said¹.

The nurse realized the overdose after seeing five other syringes meant for the vial².

No adverse effects so far

Immediately after being notified of the COVID-19 vaccine overdose, the attending physician started monitoring the patient’s health.

Dr. Antonella Vicenti, the director of infectious disease at Noa Hospital where it all happened, said the patient did not develop a fever or experience pain, save for some discomfort at the injection site¹.

The woman remained in the emergency room for 24 hours, where she received fluids, anti-fever, and ant-inflammatory medicines as preventive measures. She was discharged the following day, Monday.

For now, Dr. Vicenti is confident the patient “will certainly not have side-effects.” However, she doesn’t know what the massive dose will do to the woman’s antibody levels and immunity against COVID-19 in the long run. Noa Hospital said they would regularly monitor the patient’s blood and immune response¹.

Pfizer’s phase 1 and 2 clinical trials showed that participants who received higher doses than recommended didn’t develop any severe adverse reactions³.

It’s not the first reported case of COVID-19 vaccine overdose

What happened in Tuscany was not the first reported case of COVID-19 vaccine overdose.

In December of 2020, news broke that eight healthcare workers in an elderly home in Germany received five times the standard dose of the Pfizer vaccine. Four had been rushed to the hospital after developing flu-like symptoms⁴.

In April 2021, 77 inmates of the Iowa State Penitentiary received six times the usual Pfizer vaccine dose. Prison officials said none of the inmates needed hospitalization, but some experienced side effects like fever and body aches⁵.

Mistakes in vaccination have other consequences

Besides the potential health risks, authorities fear that COVID-19 vaccine overdose will fuel the public’s hesitancy towards vaccination.

They also worry about vaccine wastage. With many countries far behind the vaccination program, every dose counts.

Health authorities said they understand that medical front liners are sometimes pushed to their limits, and so lapses are bound to happen, but they also emphasized an overdose should never happen.

Safety when receiving the COVID-19 shot

Before getting the vaccine, experts encourage people to talk to their doctor first. They need to discuss the possibility of allergic reactions and raise questions regarding medications.

During the appointment, continue to follow safety protocols: wear a face mask and face shield, and practice physical distancing. Communicate with the healthcare worker about any condition that may warrant precautionary measures.

After receiving the shot, stay in the facility for about 15 to 30 minutes. The healthcare workers will monitor for severe allergic reactions.

Finally, understand that side-effects, like pain injection site, fever, and muscle aches, may occur. In case the symptoms persist or worsen, don’t hesitate to contact your doctor immediately. – Hello Doctor

More Health News here.

Hello Health Group does not provide medical advice, diagnosis or treatment.


1) Distracted nurse gives woman 6 doses of COVID vaccine in a single shot
Accessed May 12, 2021

2) Italian woman mistakenly given 6 doses of Pfizer vaccine in one shot
Accessed May 12, 2021

3) Phase I/II study of COVID-19 RNA vaccine BNT162b1 in adults
Accessed May 12, 2021

4) Vaccine overdose puts German care workers in hospital
Accessed May 12, 2021

5) Dozens of inmates at an Iowa prison were sickened after they were given overdoses of the COVID-19 vaccine
Accessed May 12, 2021

6) What you need to know before, during and after receiving a COVID-19 vaccine
Accessed May 12, 2021

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Written by Lorraine Bunag, R.N. Updated May 13
Fact Checked by Hello Doctor Medical Panel