Nebulizer unit with medication reservoir for use in a nebulizer, comprising - an aerosol generator for atomizing a medication liquid having a feed side, which is in contact with the medication liquid present there, and a discharge side, at which the mist formed is emitted and which is retained between a sealing ring at the supply side and a retaining structure at the discharge side, - a housing, which encloses the aerosol generator, the sealing ring and the retaining structure and into which, at the supply side of the aerosol generator, the - medication reservoir is integrated, which provides in its interior a hollow volume, into which the medication liquid is introduced, and - a cap, which tightly seals the reservoir, - the cap having a closure pin, which extends into the interior space of the reservoir and - wherein a portion of the surface of the closure pin and a portion of the inner surface of the reservoir is formed complementary to one another and, when the cap is firmly fitted, form a liquid-tight closure, by means of which the inner space of the reservoir is subdivided into a first partial volume, which is delimited at one side by the aerosol generator and on another side by an end surface or a partial surface of the closure pin, as well as at least one further partial volume, and - wherein the liquid-tight closure is created by the fact that the complementary partial surfaces come to lie close to one another or one on top of the other or are pressed against one another, and - wherein at least one of the two complementary partial surfaces of the closure pin and of the inner space of the reservoir has a rubber or silicone covering. - an aerosol generator for atomizing a medication liquid having a feed side, which is in contact with the medication liquid present there, and a discharge side, at which the mist formed is emitted and which is retained between a sealing ring at the supply side and a retaining structure at the discharge side, - a housing, which encloses the aerosol generator, the sealing ring and the retaining structure and into which, at the supply side of the aerosol generator, the - medication reservoir is integrated, which provides in its interior a hollow volume, into which the medication liquid is introduced, and - a cap, which tightly seals the reservoir, - the cap having a closure pin, which extends into the interior space of the reservoir and - wherein a portion of the surface of the closure pin and a portion of the inner surface of the reservoir is formed complementary to one another and, when the cap is firmly fitted, form a liquid-tight closure, by means of which the inner space of the reservoir is subdivided into a first partial volume, which is delimited at one side by the aerosol generator and on another side by an end surface or a partial surface of the closure pin, as well as at least one further partial volume, and - wherein the liquid-tight closure is created by the fact that the complementary partial surfaces come to lie close to one another or one on top of the other or are pressed against one another, and - wherein at least one of the two complementary partial surfaces of the closure pin and of the inner space of the reservoir has a rubber or silicone covering.