Question Summary:
Will the application minoxidil / rogaine/ regaine on the head/hair break ones fast?

Question Detail:

Is it permissible to use minoxidil / rogaine/ regaine on the head/hair when fasting? Minoxidil is a treatment used to regrow hair, which is applied on the scalp. I am unsure whether it is absorbed and would affect the fast

Answer :

In the Name of Allah, the Most Gracious, the Most Merciful.
As-salāmu ‘alaykum wa-rahmatullāhi wa-barakātuh.
Minoxidil is an antihypertensive vasodilator medication and is used to treat hair loss. It is available as a generic medication and over the counter for the treatment of androgenic alopecia, a form of hair loss, in men and women.¹ The inactive ingredients are Alcohol (60% v/v), propylene glycol, purified water.²
The usage of use minoxidil / rogaine/ regaine is permissible in the state of fasting. ³
And Allah Ta’āla Knows Best
Huzaifah Deedat
Student Darul Iftaa
Lusaka, Zambia 
Checked and Approved by,
Mufti Ebrahim Desai.
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1 https://en.wikipedia.org/wiki/Minoxidil
2. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=02142c9c-8b2c-479e-8205-23d2a9c2f198
درر الحكام شرح غرر الأحكام- دار إحياء الكتب العربية (1/ 201) 3
 اعْلَمْ أَنَّ الْأَفْعَالَ الصَّادِرَةَ مِنْ الصَّائِمِ فِيمَا يَتَعَلَّقُ بِهَذَا الْبَابِ ثَلَاثَةُ أَقْسَامٍ: الْأَوَّلُ - مَا يُتَوَهَّمُ أَنَّهُ مُفْسِدٌ لَهُ وَلَيْسَ بِمُفْسِدٍ وَالثَّانِي - مَا يُفْسِدُهُ، وَلَا يُوجِبُ الْكَفَّارَةَ وَالثَّالِثُ - مَا يُفْسِدُهُ وَيُوجِبُ الْكَفَّارَةَ، وَقَدْ بَيَّنَ الْأَقْسَامَ بِالتَّرْتِيبِ وَذَكَرَ الْأَوَّلَ بِقَوْلِهِ (إنْ أَكَلَ أَوْ شَرِبَ أَوْ جَامَعَ نَاسِيًا) قَيْدٌ لِلثَّلَاثَةِ الْمَذْكُورَةِ (أَوْ احْتَلَمَ أَوْ أَنْزَلَ بِنَظَرٍ أَوْ ادَّهَنَ أَوْ اكْتَحَلَ أَوْ احْتَجَمَ
الهداية في شرح بداية المبتدي- دار احياء التراث العربي (1/ 120)
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