No matter what kind of collagen treatment you opt for, no specific one will last forever. Human-derived collagen injections can sometimes last a few months longer than bovine-derived collagen injections. Knowing that the human-derived injections are less likely to cause an allergic reaction also contributes to a higher cost.
The most appealing part about human-derived collagen for most people it that it comes from humans, not animals. Also, you have options a wider variety of options with human-derived collagen. For example, you can choose to use collagen that's been manufactured in a lab. If you're worried about having an allergic reaction to something that's foreign to your body, however, you can also use your own collagen from elsewhere in your body.
And if you're a little apprehensive about using collagen from your own body, you may want to consider something else entirely. Some human-derived collagen even comes from deceased donors [source: Shuman]. The choice is yours: Should your collagen injection come from a cow, you, or a cadaver? Whichever decision you make, you should be aware of the differences between these treatments and discuss them with your doctor.
No matter what kind of collagen you choose, most treatments will last only about three to six months. This means that in order to keep your lips looking plump, you'll have to see your doctor for injections two to four times each year and be willing to pay several hundred dollars each time [sources: Shuman].
For lots more information on collagen lip treatments, visit the links on the next page.