Reference: Fataawa Ramadhaan – Volume 2, Page 511, Fatwa No. 473
Majmoo’ Fataawa Samaahatu ash-Shaykh ‘Abdul Azeez ibn ‘Abdullaah ibn Baaz
Question: What is the ruling concerning toothpaste, ear drops, nose drops and eye drops for one who is fasting?
Response: In the Name of Allaah and all Praise is for Allaah. Cleaning the teeth with toothpaste does not break the fast just as using the miswaak doesn’t. He needs to be careful that nothing passes down [his throat] to his stomach. However, if this happens without intention, he does not have to make this fast up. The same applies to eye and ear drops, that is, they do not break the fast according to the correct of the two opinions. But, should he find the taste of these drops in his throat, it is safer to make up this fast although it is not obligatory. This [being not obligatory] is because they [the eyes and the ears] are not an inlet for food and drink. As for nose drops, then these are not permissible, as they are an inlet. Because of this, the Prophet (sal-Allaahu ‘alayhi wa sallam) said:
«Exaggerate in taking water into the nose [during ablution] except if you are fasting».
So, one who does this must make up [the fast] due to this hadeeth and that which constitutes this and thus finds its taste in his throat.
And Allaah is the Provider of Success.