Using animals for medical research

We put this question to Shaykh Muhammad ibn Saalih al-‘Uthaymeen, may Allah preserve him, who answered as follows:

“I do not see anything wrong with this, because of the general application of the words of Allah (interpretation of the meaning): ‘It is He Who created for you all that is on earth’ [al-Baqarah 2:29]. But it is essential to choose the easiest form of experimentation (that which is least painful to the animals). And Allah knows best.”