Does mouthwash break the fast?

Detailed answer

No. Rinsing your mouth with mouthwash and spitting it out does not break the fast, because nothing is swallowed. However, a liquid swirled around the whole mouth is easier to swallow by accident than toothpaste, so many scholars advise using it outside fasting hours unless there is a real need.

Why it does not break the fast

The fast is broken by what is eaten or drunk, not by something that touches the inside of the mouth and is then spat out. Rinsing the mouth is part of every wudu, including while fasting. When Umar ibn al-Khattab once feared he had spoiled his fast, the Prophet, peace be upon him, compared his case to rinsing the mouth with water while fasting, which everyone knew was harmless (Abu Dawud). At the same time, the Prophet told people to rinse the nose thoroughly "unless you are fasting" (Abu Dawud and Tirmidhi), which teaches caution.

In practice

• Best time: after suhoor and after iftar, as part of your normal routine.
• During the day: if you use it, take a small amount, keep your head forward and do not gargle at the back of the throat.
• Spit it all out and, if you like, rinse once with water.
• The taste that stays in your mouth afterwards does not matter.

What if …

… a drop goes down by accident? Many scholars hold that an unintended trace does not break the fast, as with water in your throat during wudu. Swallowing on purpose does break it.

… my dentist prescribed a mouth rinse? A medical rinse, for example after a tooth extraction, may be used during the day with the same care. Follow the advice of your dentist, ideally one who understands fasting, and see going to the dentist while fasting.

Tips for fresh breath

Mouthwash only hides odour for a short time. Brushing at night, cleaning your tongue, drinking enough water between iftar and suhoor and using a miswak during the day do more to keep your mouth fresh. For the general rule on cleaning products, see also does toothpaste break the fast.