Most of the scholars are of the view that the sick person is not allowed to break his fast in Ramadan unless the sickness is severe. For more, please see the detailed answer.

The scholars ruled that the fast is not broken by using a puffer as asthma medication. Oxygen may be used as asthma medication when fasting with no problems. If you use vaporizers, you should break your fast and make up that day later. Using capsules invalidates the fast because some of the powder mixes with the saliva and goes down into the stomach.

If fasting causes you to vomit or become dizzy because of physical weakness, you can break your fast but you have to make up for the missed days later.