| 摘要 |
A powder inhalator (1) for pulverous agents comprises a means for providing a single dose of the agent in a passage (3, 5, 4) extending from an inlet to an outlet. A valve assembly in the passage (3, 5, 4) is arranged to keep the passage closed except if a negative pressure of a given size is generated in a portion (5, 4) of the passage (3, 5, 4) downstream of the valve assembly. The valve assembly comprises a valve element (6) displaceable between a closed position and an open position in which it restricts the flow of air in comparison with the flow prevailing immediately upon the opening of the passage. Also disclosed is a corresponding method of administration. |
