Praise be to Allah.
We ask Allah, may He be exalted, to give you and your father, and all the Muslims, well-being, for He is most generous and kind.
“Smokeless tobacco” is a type of tobacco that is not burned and may be mixed with other substances; it is used by some people who place it in their mouths. The ruling on this substance is no different from the ruling on cigarettes.
Shaykh ‘Abd-Allah ibn Jibreen (may Allah have mercy on him) said:
There is no doubt that cigarettes, nargilah (shisha), smokeless tobacco and the like are haram, because they are all evil and unlawful. Allah says (interpretation of the meaning):
“He allows them as lawful At-Tayyibât (i.e. all good and lawful as regards things, deeds, beliefs, persons, foods), and prohibits them as unlawful Al-Khabâ’ith (i.e. all evil and unlawful as regards things, deeds, beliefs, persons and foods)”
[al-A ‘raaf 7:157].
And because they damage people’s health and cause serious diseases that may lead to death, and Allah says (interpretation of the meaning):
“And do not kill yourselves”
“and do not throw yourselves into destruction”
And because it is extravagance and a waste of money on something that is of no benefit, and the spendthrifts are the brothers of the devils (cf. 17:27). We advise anyone who is tested with any of these things to repent and give it up immediately, and to resolve not to go back to it, and to seek the help of Allah in quitting it, and to be patient for a few days until he is able to give it up completely and put an end to the pain that it causes him. And Allah is the Healer. End quote from Fataawa Islamiyyah, 3/446
Smokeless tobacco breaks the fast, because when it is placed in the mouth it dissolves and some particles of it enter the stomach with the saliva.
The scholars of the Standing Committee were asked:
What is the ruling on using smokeless tobacco in general, and what is the ruling on using it during the day in Ramadan in particular? Does it break the fast if someone uses it during the day in Ramadan? Please note that some of the people of Tihaamah Qahtaan use smokeless tobacco during the day in Ramadan and claim that it does not break the fast.
They replied: Smokeless tobacco is an evil substance because it is composed of an evil, haraam substance. If it is used by one who is fasting, in addition to it being sinful, it also breaks his fast, the same as any other substance that breaks the fast.
And Allah is the source of strength. May Allah sent blessings and peace upon our Prophet Muhammad and his Family and Companions. End quote.
Shaykh ‘Abd al-‘Azeez ibn ‘Abd-Allah Aal al-Shaykh, Shaykh ‘Abd-Allah ibn Ghadyaan, Shaykh Saalih al-Fawzaan
Fataawa al-Lajnah al-Daa’imah, vol. 1, 22/142
Based on this, your father has to make up the days that he broke the fast by using smokeless tobacco during last Ramadan and the one before. But if your father did not know that smokeless tobacco breaks the fast, then his fast is valid, because the one who fasts is excused for ignorance of what breaks the fast.
For more information please see the answer to question no. 93866
You should try to advise your father to give up this evil substance. Tell him that it is of no benefit in treating insomnia and anxiety; rather it causes more insomnia and anxiety. We ask Allah to guide your father and accept his repentance.
And Allah knows best.