Question: If one heeds a doctor’s advice on the deathbed, to take medicine that contains meat ingredients, will this affect one’s ability to reach Pure Land?
Answer: It is best to reduce and eventually abstain from animal products and by-products when both alive and on the deathbed, although the Buddha did rule in the basic Vinaya (precepts for monastics in the Theravada tradition) that meat can be purposely sought and eaten for medical purposes. If this is applicable to monastics, it should apply to laity too. Of course, the animals involved should not be directly killed for oneself. Meat-free alternatives should ideally first be sought too.
In the Mahayana tradition though, in order to cultivate greater compassion with the Bodhisattva Precepts as a guide, even if partially, meat is best avoided, especially if already on the deathbed, as there should be minimisation of being directly OR indirectly linked to the suffering of animals by being part of supply and demand. If as enquired, for one who is already dying, there is perhaps not much point in indirectly ‘demanding’ the dying of more sentient beings for oneself by continual purchase, as this is ultimately in vain.
Yet, as the core essentials to reach Pure Land are the Three Provisions (Faith, Aspiration and Practice: http://purelanders.com/2010/04/01/the-three-provisions-of-faith-aspiration-practice), vegetarianism (and veganism) is not an absolute must, though it is a powerful practice for accumulating merits and dissolving negative karma. When dying, it is best to not create more of the slightest negative karma, even by diet. Much meat-eating can create negative karma that makes it harder to nurture the Three Provisions, but it might not be strong enough to create a substantial problem, especially if the provisions are stronger. It is worth noting that with strong provisions, there will be no craving for meat too.
Must Pure Land Practitioners Be Vegetarians? (With Great Master Yinguang’s Advice)