In spite of Single Use labeling syringe and lancet makers put on their products, you can safely reuse syringes and lancets. Each time you use them, however, they become a little more dull, resulting in a more painful use. Discard after they become too uncomfortable to use.
Some people report getting between five and ten uses from a syringe and somewhat less from a lancet.
If cost is an issue for you, this could be a way to make your healthcare dollars work harder. This is even more important if you reuse your lancet. Do not clean the lancet after use. Just leave it in the lancing device. You already have any germs that might end up on the lancet tip.