Small unit dosage plunger rod stops

A system for modifying a syringe to deliver a measured dose that is less than a full volume of a barrel of the syringe, the system comprising:

• a first plunger rod stop comprising:
• an attachment clip configured to removably attach to the barrel;
• and
• an elongated member extending proximally from the attachment clip, the elongated member having a bearing surface configured to bear against a plunger of the syringe when the attachment clip is attached to the barrel, thereby preventing the plunger from being depressed past a first position with respect to the barrel;
• and
• a second plunger rod stop substantially similar to the first plunger rod stop, wherein the elongated member of the second plunger rod stop has a length that is shorter than a length of the elongated member of the first plunger rod stop, such that the bearing surface of the second plunger stop rod prevents the plunger from being depressed past a second position with respect to the barrel,
• wherein depressing the plunger from the first position to the second position causes a measured dose of liquid contained in the barrel to be expelled from the barrel.