Typical contents might include 1/2 cc of each of the following:

• Brompheniramine (think Dimatapp / antihistamine)                     
• Dexamethasone 8 (dex 8 is a long acting steroid to reduce swelling of sinus membranes)
• Dexamethasone 4 (dex4 is a faster acting steroid)  
• Diphenhydramine (benedryl. This might or might not be included, depends on the doctor and the patient) 

Note: These are not necessarily the actual drugs that will be used in YOUR sinus cocktail. This recipe is actually a sample "sinus cocktail" recipe found in the health section of this link. This recipe is based on the classes / types of drugs expected to be in the average sinus cocktail. There is no standard recipe for the sinus cocktail across the medical community. However, there is a standard set of the TYPES of drugs that go into the sinus cocktail, and the recipe above illustrates the TYPES of drugs you can expect in the sinus cocktail shot (medication) your doctor would give to you.