Venting of pharmaceutical drug delivery device for air flow and humidity control

1. A pharmaceutical drug delivery device comprising:

a drug delivery device body;

a fluid outlet nozzle attached to the drug delivery device body;

a fluid jet ejection cartridge containing a liquid pharmaceutical drug is disposed in the drug delivery device body, wherein a fluid ejection head is attached to the fluid jet ejection cartridge and the fluid ejection head is in fluid flow communication with the fluid outlet nozzle; and

an elongate, serpentine air flow path between an outer surface of the fluid jet ejection cartridge and an inner surface of the fluid outlet nozzle, wherein the elongate, serpentine air flow path provides a reduced pressure differential adjacent to a surface of the fluid ejection head upon use of the drug delivery device and provides a humidification zone.

2. The pharmaceutical drug delivery device of claim 1 , wherein the elongate, serpentine air flow path has a length to cross-sectional area ratio of greater than 30:1 to about 100:1.

3. The pharmaceutical drug delivery device of claim 1 , wherein the elongate, serpentine air flow path is provided by a multi-chamber sealing material disposed in the fluid outlet nozzle between an interior surface of the fluid outlet nozzle and an exterior surface of the fluid jet ejection cartridge, wherein the multi-chamber sealing material comprises air chambers and notches for air flow between adjacent air chambers.

4. The pharmaceutical drug delivery device of claim 3 , wherein the elongate, serpentine air flow path is provided between an exterior surface of the fluid jet ejection cartridge through the notches and air chambers of the multi-chamber sealing material.

5. The pharmaceutical drug delivery device of claim 1 , wherein the elongate, serpentine air flow path is provided between an interior surface of the fluid outlet nozzle and an exterior surface of a sealing material disposed in the fluid outlet nozzle adjacent to the fluid jet ejection cartridge.

6. The pharmaceutical drug delivery device of claim 1 , further comprising a plug to cap off the fluid outlet nozzle and create the humidification zone in the drug delivery device between uses.

7. A method for reducing a pressure differential on a fluid jet ejection head for a nasal spray device, the method comprising:

providing a pharmaceutical drug delivery device having a fluid outlet nozzle attached to a drug delivery device body; a fluid jet ejection cartridge disposed in the drug delivery device body, the fluid jet ejection cartridge containing the fluid ejection head in fluid flow communication with the fluid outlet nozzle and a pharmaceutical drug in the fluid jet ejection cartridge;

inserting a sealing material between an outer surface of the fluid jet ejection cartridge and an inner surface of the fluid outlet nozzle, wherein the sealing material contains an elongate, serpentine air flow path therein to provide a reduced pressure differential adjacent to a surface of the fluid ejection head upon use of the drug delivery device; and

activating the nasal spray device while flowing air through the drug delivery device body and elongate, serpentine air flow path when the fluid outlet nozzle is inserted into the nasal passage of a user thereby preventing fluid from drooling from the fluid ejection head.

8. The method of claim 7 , wherein the elongate, serpentine air flow path has a length to cross-sectional area ratio of about 30:1 to about 100:1.

9. The method of claim 7 , wherein the reduced pressure differential is provided by a multi-chamber sealing material disposed in the fluid outlet nozzle, wherein the multi-chamber sealing material comprises air chambers and notches for air flow between adjacent air chambers.

10. The method of claim 9 , wherein the reduced pressure differential is provided between the outer surface of the fluid jet ejection cartridge and the air chambers of the multi-chamber sealing material.

11. The method of claim 7 , wherein the reduced pressure differential is provided between the inner surface of the fluid outlet nozzle and an exterior surface of a sealing material.

12. A method for preventing a surface of a fluid jet ejection head for a nasal spray device from drying out between uses, the method comprising:

providing a pharmaceutical drug delivery device having a fluid outlet nozzle attached to a drug delivery device body; a fluid jet ejection cartridge disposed in the drug delivery device body, the fluid jet ejection cartridge containing the fluid ejection head in fluid flow communication with the fluid outlet nozzle and a pharmaceutical drug in the fluid jet ejection cartridge;

inserting a sealing material between an outer surface of the fluid jet ejection cartridge and an inner surface of the fluid outlet nozzle, wherein the sealing material contains an elongate, serpentine air flow path therein to provide a humidification zone in the drug delivery device adjacent to a surface of the fluid ejection head between uses of the drug delivery device; and

plugging the fluid outlet nozzle with a cap to prevent drying out of the surface of the fluid jet ejection head.

13. The method of claim 12 , wherein the elongate, serpentine air flow path has a length to cross-sectional area ratio of about 30:1 to about 100:1.

14. The method of claim 12 , wherein the humidification zone is provided by a multi-chamber sealing material disposed in the fluid outlet nozzle, wherein the multi-chamber sealing material comprises air chambers and notches for air flow between adjacent air chambers.

15. The method of claim 14 , wherein the humidification zone is provided between the outer surface of the fluid jet ejection cartridge and chambers of the multi-chamber sealing material.

16. The method of claim 12 , wherein the humidification zone is provided between the inner surface of the fluid outlet nozzle and an exterior surface of a sealing material.