2. Press your nostrils together for at least 10 minutes. 3. Use a cold compress on the bridge of your nose to constrict blood vessels. 4. If the bleeding continues, use a nasal decongestant spray.

Some medicines, among them beta blockers prescribed for high blood pressure, can constrict blood vessels and worsen the problem, so a medication switch may be needed, said Bernatsky.

“Shovelling snow and cold weather can strain the heart, raise blood pressure and constrict blood vessels, increasing the risk of heart attack, especially for those with heart disease,” he said. “I ...

The small study, involving 25 people, suggests that exposure to ozone gas and fine particles, such as those found in car exhaust, can constrict blood vessels by two to four per cent.

But oral decongestants must be absorbed through the gastrointestinal tract before they hit the blood stream, and they cause blood vessels to constrict throughout the body – not just the nose.