Question # 74: Does extraction of blood for medical test purposes break fast?
bismi-llahi r-raḥmani r-raḥīm,
Assalamu ‘laikum warahmatullahi wabarakatuh,
All praise and thanks are due to Allah (سبحانه و تعالى), and peace and blessings be upon His Messenger (صلى الله عليه و سلم).
First of all, we implore Allah (سبحانه و تعالى) to help us serve His cause and render our work for His sake.
Shorter Answer: The fasting person does not invalidate his fast due to the removal of blood for the purpose of a blood test except for in the case of blood transfusion or cupping (hijaamah).
Long Answer: Shaykh Ibn ‘Uthaymeen said “The fasting person does not invalidate his fast due to the removal of blood for the purpose of a blood test, because the doctor needs to take blood from the sick person in order to do tests on it, so this does not break the fast. It is only a small amount of blood which does not affect the body in the same way cupping (hijaamah) does, so it does not break the fast. The fundamental principle is that the fast remains valid, and we cannot make it invalid without some legal evidence, and there is no evidence that a fasting person breaks his fast by such a small amount of blood.
But as for taking a lot of blood from a fasting person for the purpose of giving a transfusion to another person who is in need of it for example, if a large quantity of blood was taken which has the same effect on his body as cupping (hijaamah), then his fast will be broken thereby.
Based upon this, if the fast is an obligatory one, then it is not permissible for a person to donate this large amount of blood to anyone, unless this person to whom blood is donated is in danger and it is not possible for him to wait until after sunset. This would be if the doctors have determined that the blood of this fasting person will benefit him and remove the harm from the patient. In these circumstances, there is no objection to him donating his blood, breaking his fast, and eating and drinking, so that his strength will return to him. He must also make up for the day in which he broke his fast. And Allah knows best.” (Fatawa Arkan-ul-Islam)
Shaykh ibn Baaz said “The fast is not nullified for this (analysis), rather it is exempted from. This is because it is a necessity and nor from that which is known, from the pure shari’ah, to break the fast” (‘Ramadhaan Fataawa’ The Permanent Committee for Islamic Research and Fataawa)
Allahu A’lam (Allah (سبحانه و تعالى) knows best) and all Perfections belong to Allah, and all mistakes belong to me alone. May Allah (سبحانه و تعالى) forgive me, Ameen.