The invention faces the technical problem of reducing the uncertainty over exact doses ejected from a medical device and at the same time providing a homogeneous, but controlled mixture of at least two fluids while a simple production should be maintained. A medical device comprising a first valve, a second valve, a first pre-valve ullage, a second pre-valve ullage, a post-valve ullage with a first end and a second end and a needle is presented. The first pre-valve ullage is connected to the post-valve ullage by the first valve and the second pre-valve ullage is connected to the post-valve ullage by the second valve. A first fluid is guidable from the first pre-valve ullage to the post-valve ullage and a second fluid is guidable from the second pre-valve ullage to the post-valve ullage.
