He has forbidden you only the Maytatah (dead animals), and blood, and the flesh of swine, and that which is slaughtered as a scrifice for others than Allah (or has been slaughtered for idols, etc., on which Allah's Name has not been mentioned while slaughtering). But if one is forced by necessity without wilful disobedience nor transgressing due limits, then there is no sin on him. Truly, Allah is Oft-Forgiving, Most Merciful.