I recently had a conversation with a friend about animal testing. She repeated a common argument vegans hear on the matter: if you're against animal testing, you shouldn't take any medicine that has been tested on animals; that is, all medicine.
This is based on a faulty but familiar misunderstanding of why vegans avoid products that have been tested on animals. The premise of this argument is that veganism is based around a specific moral code that forbids the consumption of animals, animal products, and things that are tested on animals. Making exceptions, even life-saving exceptions, are therefore indulging in hypocrisy: "I won't use things that are tested on animals, except for..." And hypocrisy is, of course, the ultimate sin.
However, veganism is not just an arbitrary code that vegans strive to meet. It is not a purity test. Vegans abstain from certain products for a specific purpose: to prevent animal suffering. The vegan "moral code" is a practical one that has a goal, not a line in the sand adhered to for dogmatic reasons.
There are three types of animal suffering:
Direct suffering. This would be things that result directly from the exploitation of animals, such as meat, wool, leather, eggs, and milk. Obviously, vegans would object to consuming these things, and by opting out we reduce the demand for them.
Replaceable indirect suffering. This category includes, for example, soaps or shampoos tested on animals, for which there are cruelty-free alternatives. The product you actually take home didn't harm any animal directly, but at some point in the past development of the product, animals were harmed. Choosing the alternatives ("voting with our dollars") sends a message to producers, and reduces demand for animal-tested products.
Irreplaceable indirect suffering. This is the category medicine falls in. Animal testing is government-mandated for medicines. As above, the products do not come directly from harming animals, but at some historical point animals were harmed. However, there is no alternative available that was not tested on animals. As such, market signals do not apply. We can't "vote with our dollars," because in this race there are no other candidates. Buying or not buying medicine that was tested on animals does nothing to stop animal suffering, as regardless of whether people want cruelty-free medicine, and regardless of whether producers want cruelty-free medicine, they have no choice in the matter because of government regulations and the animals in question are already dead. Even while we hope for an end to animal testing and work towards that goal, and as we may personally mourn the animal suffering, there is no practical reason not to take medicine that was tested on animals in the past. In fact, there is an eminently practical reason to do so: we're no good to the animals if we're dead.
Veganism is not about moral purity, it is about stopping unnecessary animal suffering. Not eating meat does that. Buying cruelty-free options does that. Dying rather than take an antibiotic that was required by law to be tested on animals does nothing. When regulations change and we have options, we will take them.