Low concentration delivery of an ergoline derivative for treatment of a headache

1. A parenteral pharmaceutical composition comprising dihydroergotamine or a pharmaceutically acceptable salt thereof at a concentration of about 1 mg/mL and one or more pH maintaining or pH adjusting agents, wherein pH of the composition is between about 3 to about 5, the composition being contained in a preassembled, prefilled, single-use delivery device that is capable of delivering a dose of between about 0.5 to about 3 mg of the dihydroergotamine or the pharmaceutically acceptable salt thereof to a patient and is not user adjustable with respect to dosage or dosing rate.

2. The composition of claim 1 , wherein the one or more pH maintaining or pH adjusting agents includes a buffer.

3. The composition of claim 2 , wherein pH of the composition is maintained between 3.4 and 4.9.

4. The composition of claim 1 , wherein pH of the composition is maintained between 3.4 and 4.9.

5. The composition of claim 1 , wherein the dihydroergotamine or the pharmaceutically acceptable salt thereof is dihydroergotamine mesylate.

6. The composition of claim 5 , wherein the dose is about 1 mg of dihydroergotamine mesylate.

7. The composition of claim 6 , wherein the single-use delivery device is an autoinjector that includes a tension spring, and a rate of dosing depends on the degree of tension in the tension spring.

8. The composition of claim 7 , wherein the tension spring has a predetermined amount of tension so as to provide a desired dosing rate.

9. The composition of claim 8 , wherein the predetermined amount of tension is preloaded.

10. The composition of claim 6 , wherein the single-use delivery device is an autoinjector that includes a dosing mechanism comprising an injection spring having a degree of compression applied thereto, and a rate of dosing that depends on the degree of compression applied to the injection spring.

11. The composition of claim 10 , wherein the degree of compression of the injection spring is predetermined so as to provide a predetermined dosing rate and is not user adjustable.

12. The composition of claim 1 , wherein the one or more pH maintaining or pH adjusting agents prevent any sudden change in pH of the composition.

13. The composition of claim 1 , wherein the single-use delivery device further comprises a trigger mechanism for actuating an actuating lever maintained under pressure in an armed position.

14. The composition of claim 1 , wherein the composition is contained in the single-use delivery device by a plunger.

15. The composition of claim 1 , wherein the composition is contained in the single-use delivery device by a plunger until activated by a trigger.

16. The composition of claim 15 wherein the single-use delivery device further comprises a pawl member that releasably interfaces with a retainer in an armed position until the pawl member is released from the retainer by the trigger to activate the plunger.

17. The composition of claim 15 , wherein the trigger activates a piston rod depressing the plunger and delivering the dose through an injection needle.

18. The composition of claim 1 , wherein the single-use delivery device further comprises a moveable safety shield that is moveable about an injection needle to protect against inadvertent contact with the injection needle.

19. The composition of claim 1 , wherein the single-use delivery device further comprises a piston rod retained in an armed position keeping a tension spring under compression, the piston rod being in contact with a plunger, and when a trigger is actuated, the piston rod is released from its retainer and urged forward by the tension spring.

20. The composition of claim 1 , wherein the single-use delivery device further comprises a suction cup facilitating removal of a safety cap.