Reusing same toothbrush after a cold? Doctor warns it could be dangerous: Here's how to reduce reinfection risk

According to a doctor, after suffering from a cold, it's time for a new toothbrush if you wish to maintain good oral health and prevent the spread of germs.

Dr Kunal Sood, an anesthesiology and interventional pain medicine physician, shared an Instagram post on April 3, 2025, titled 'When you find out reusing the same toothbrush after a cold may expose you to lingering microbes'. He went on to share how 'staying mindful of toothbrush hygiene can help minimise exposure to lingering microbes'.

Brushing with the same toothbrush after a cold can be potentially hazardous to your health. Find out why. (Representative picture: Freepik)

Your toothbrush holding onto germs after a cold?

According to Dr Sood, it is a good practice to replace your toothbrush after an illness to prevent the spread of germs. He said: “Could your toothbrush be holding onto germs after a cold? While there's no direct proof that viruses stay infectious on a toothbrush, research confirms they can harbour bacteria, fungi, and other pathogens — some even forming resilient biofilms. When you have a cold this can make you even more vulnerable to other infections during that time.”

Tips for maintaining your toothbrush

According to him, 'to reduce the risk of reinfection', here's what you should do:

1. Rinse your toothbrush thoroughly after each use.

2. Store the toothbrush upright in a dry, ventilated area.

3. Disinfect your toothbrush with UV light, chlorhexidine, or steam.

4. Replace the toothbrush after an illness.

According to Dr Sood, here's how often you should replace your toothbrush:

1. Every 3-4 months or sooner if the bristles are worn out.

2. Worn-out bristles don't clean as effectively and can leave more plaque behind.

3. Toothbrushes collect microbes over time, even if they look clean.

4. A fresh toothbrush helps maintain oral health and may even lower the risk of some systemic diseases.

Apart from checking your toothbrush regularly for wear and tear, you should also avoid some common brushing mistakes for good oral health. Click here to learn more about common brushing and flossing mistakes.

Note to readers: This article is for informational purposes only and not a substitute for professional medical advice. Always seek the advice of your doctor with any questions about a medical condition.