Does taking an injection invalidate the fast?

No, taking an injection does not invalidate the fast. This is because the injection will not enter the Jowf (digestive tract) of the body. In the Hanafi Madhab a fast is nullified when liquids or solids reach the Jowf.

وَكُلُوا وَاشْرَبُوا حَتَّى يَتَبَيَّنَ لَكُمُ الْخَيْطُ الْأَبْيَضُ مِنَ الْخَيْطِ الْأَسْوَدِ مِنَ الْفَجْرِ ثُمَّ أَتِمُّوا الصِّيَامَ إِلَى اللَّيْلِ

And eat and drink until the white threat becomes distinct from the black thread at dawn. Then complete your fast until the night. (Surah al-Baqarah, 187).

In the Hanafi Madhab something entering the digestive tract (Jowf) or the head invalidates the fast.  Things entering the body from elsewhere do not invalidate the fast, even if they enter the blood stream. Therefore, an injection does not invalidate the fast.

وَلَوْ دَاوَى جَائِفَةً أَوْ آمَّةً بِدَوَاءٍ فَوَصَلَ إلَى جَوْفِهِ أَوْ دِمَاغِهِ أَفْطَرَ (الهداية شرح بداية المبتدي)

If he applies medication to a stomach or head injury and it enters the cavity then the fast is invalidated. (Imam al-Marghinani, al-Hidaayah).

In this Masalah (legal ruling) it is made clear that introducing something, in this case medicine, to a wound will not invalidate the fast, unless it enters the stomach or head itself. So, an injection does not invalidate the fast since it does not enter the head or stomach directly.

The Ayah above shows that eating and drinking invalidates the fast. However there is no evidence to say things entering the body in other ways also invalidates the fast. Thus, it is a lack of evidence that brought the Hanafi scholars to the conclusion that injections and the like do not invalidate the fast. However, the following Hadith also supports the Hanafi position.

قَالَ أَبُو بَكْرٍ: قَالَ: الَّذِي حَدَّثَنِي لَقَدْ رَأَيْتُ رَسُولَ اللَّهِ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ بِالْعَرْجِ يَصُبُّ عَلَى رَأْسِهِ الْمَاءَ، وَهُوَ صَائِمٌ مِنَ الْعَطَشِ، أَوْ مِنَ الْحَرِّ

Abu Bakr (bin Abd al-Rahmaan) said one of the Sahabah informed me that he saw the Prophet ﷺ, at al-Arj, pour water over his head whilst he was fasting, due to thirst or heat. (Abu Dawood 2365, Sahih).

Imam Ali al-Qari mentioned in the commentary of this Hadith that anything entering through the pores of the body will not invalidate the fast.

وَالْمُفْطِرُ الدَّاخِلُ مِنَ الْمَنَافِذِ كَالْمُدْخَلِ وَالْمُخْرَجِ لَا مِنَ الْمَسَامِّ الَّذِي هُوَ جَمِيعُ الْبَدَنِ (مرقاة المفاتيح)

The invalidators of the fast are things that enter through openings, like the place of entry and exit. Not (through) the pores that cover the entire body. (Mirqaat al-Mafateeh).

وَالدَّاخِلُ مِنْ الْمَسَامِّ لَا يُنَافِي كَمَا لَوْ اغْتَسَلَ بِالْمَاءِ الْبَارِدِ (الهداية شرح بداية المبتدي)

Things entering through the pores do not invalidate the fast. Just like a person washing himself with cold water (does not invalidate). (Imam al-Marghinani, al-Hidaayah).

In the above Nusoos (texts) we see that something entering the body through the pores does not nullify the fast. Hanafi scholars considered an injection to be similar to this. Thus, they determined than an injection does not invalidate the fast.

This ruling is incredibly important since many people refrain from fasting as they think the injection they require will nullify the fast. Therefore, they miss out on the great reward and benefit of fasting. More significantly they fail to fulfil a religious obligation.

And Allah (Most High) Knows best.

– Answered by Shaykh Noorud-deen (09.03.2021)

See also:

Hadith about the Prophet ﷺ pouring cold water over himself whilst fasting

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