Short answer
Yes. Strong painkillers such as morphine, given by a doctor to relieve severe pain, are allowed even if they make the patient drowsy. The aim is relief, which is treatment. Giving a dose with the aim of ending life is euthanasia and is haram. Where possible, families can ask doctors to balance comfort with the patient's alertness for prayer and the shahada.
Using a narcotic as medicine for a real need is permitted, and severe pain is such a need. Relief given at the dose a doctor judges necessary is lawful even if it brings drowsiness. Intending to hasten death is forbidden.
The four schools agree on this.
Explanation
Allah wants ease for His servants, and He does not burden a soul beyond its capacity. The Prophet ﷺ told people to seek treatment and taught a man in pain to place his hand on the place that hurt and say, "I seek refuge in Allah and His power from the evil of what I feel and fear." Relieving pain is part of caring for the sick.
Morphine and similar drugs are narcotics. The Hanafi texts forbid narcotics taken for pleasure, but allow them as medicine for a real need, at the amount needed. Severe pain from cancer or another terminal illness is a clear need. So palliative care with morphine, and even sedation when nothing else controls the suffering, is allowed under a qualified doctor.
The line is intention and dose. Giving the dose a doctor judges necessary for pain is treatment, even if it may have side effects. Deliberately giving an overdose to end the patient's life is killing, which is haram even if the patient asks. See euthanasia and life support.
Practical points for families:
- ask the care team whether pain can be controlled while keeping the patient alert at times, so they can pray as they are able, make dhikr and hear the shahada
- a conscious patient prays as they can, sitting or lying down and nodding the head for ruku and sujud; in the Hanafi school, if they cannot even nod, the prayer is put off rather than done with the eyes (see praying when sick)
- ask a mufti about prayers missed while heavily sedated
- sit with them, recite Quran and say the shahada gently near them (see when someone is dying)
Every case is different, so follow a qualified doctor's advice on medication and ask a mufti about the religious details.
Ask a mufti about your own case. This answer explains the general ruling. When the details of your situation matter, as they do here, ask a qualified mufti and give them the full facts. Where to ask a scholar.
The evidence
Quran, Surah Al-Baqara 2:185
شَهْرُ رَمَضَانَ ٱلَّذِىٓ أُنزِلَ فِيهِ ٱلْقُرْءَانُ هُدًۭى لِّلنَّاسِ وَبَيِّنَٰتٍۢ مِّنَ ٱلْهُدَىٰ وَٱلْفُرْقَانِ ۚ فَمَن شَهِدَ مِنكُمُ ٱلشَّهْرَ فَلْيَصُمْهُ ۖ وَمَن كَانَ مَرِيضًا أَوْ عَلَىٰ سَفَرٍۢ فَعِدَّةٌۭ مِّنْ أَيَّامٍ أُخَرَ ۗ يُرِيدُ ٱللَّهُ بِكُمُ ٱلْيُسْرَ وَلَا يُرِيدُ بِكُمُ ٱلْعُسْرَ وَلِتُكْمِلُوا۟ ٱلْعِدَّةَ وَلِتُكَبِّرُوا۟ ٱللَّهَ عَلَىٰ مَا هَدَىٰكُمْ وَلَعَلَّكُمْ تَشْكُرُونَ ﴿١٨٥﴾
The month of Ramadhan [is that] in which was revealed the Qur'an, a guidance for the people and clear proofs of guidance and criterion. So whoever sights [the new moon of] the month, let him fast it; and whoever is ill or on a journey - then an equal number of other days. Allah intends for you ease and does not intend for you hardship and [wants] for you to complete the period and to glorify Allah for that [to] which He has guided you; and perhaps you will be grateful.
Relieving hardship fits the purpose of the Shariah.
Quran, Surah Al-Baqara 2:173
إِنَّمَا حَرَّمَ عَلَيْكُمُ ٱلْمَيْتَةَ وَٱلدَّمَ وَلَحْمَ ٱلْخِنزِيرِ وَمَآ أُهِلَّ بِهِۦ لِغَيْرِ ٱللَّهِ ۖ فَمَنِ ٱضْطُرَّ غَيْرَ بَاغٍۢ وَلَا عَادٍۢ فَلَآ إِثْمَ عَلَيْهِ ۚ إِنَّ ٱللَّهَ غَفُورٌۭ رَّحِيمٌ ﴿١٧٣﴾
He has only forbidden to you dead animals, blood, the flesh of swine, and that which has been dedicated to other than Allah. But whoever is forced [by necessity], neither desiring [it] nor transgressing [its limit], there is no sin upon him. Indeed, Allah is Forgiving and Merciful.
Necessity permits what is otherwise restricted, within its limit.
Sahih Muslim 2202
Sahih... أعوذ بالله وقدرته من شر ما أجد وأحاذر ...
"I seek refuge in Allah and His power from the evil of what I feel and what I fear."
The Prophet taught a remedy for pain, showing that relief is sought.
Jami' at-Tirmidhi 2038
Graded sahih... نعم يا عباد الله تداووا ...
"Yes, servants of Allah, seek treatment."
Pain relief is a form of treatment.
Where the ruling is recorded
- Radd al-Muhtar (Ibn Abidin), Kitab al-Ashriba, on banj and opium. Narcotics are forbidden for pleasure but allowed as medicine for a need.
- al-Fatawa al-Hindiyya, Kitab al-Karahiyya, chapter on treatment. Treatment with medicines for pain and illness is permitted.
Checked by our team. For a more accurate answer to your own situation, consult a scholar. Quran translation by Sahih International. Hadith Arabic from the standard editions of the six books and the Muwatta, with gradings as recorded there; the English is our own rendering. Spotted a mistake? Tell us.