Various masaail of fasting

Fasting so that one's dua will be answered

Q: The Prophet (Sallallahu Alayhi Wasallam) said that the dua of a fasting person is answered. It's borne on the clouds and the gates of heaven are opened for it, and Allah (Ta'ala) says "By my glory, I will grant you help even if it may be after sometime". Can I fast with the intention that my dua will be answered, or is that disliked? Any help will be greatly appreciated.

19 hour fast

Q: We live in a small northern town in Canada . We are fasting for 19 hours a day. This is causing undue hardship on us as the long days during summer are combined with a lack of sleep. Esha is at 12pm. We are concerned about dehydration and experience extreme exhaustion . Is there a fatwa which exempts such long hours of Fasting? Could we follow the fasting hours of Mecca?

Taking sublingual tablets to quit drugs

Q: I would like to ask a question regarding Fasting (Sawm) and taking a sublingual tablets to quit drugs. The question is as follows:

May I fast if I take a sublingual tablet in the morning after suhur? The sublingual tablets name is Subutex 2mg it reduces cravings for opium
users. I would really like to fast. I would just like to know if is permissible for me for I only need to take this tablet for 7 consecutive days.