Is It Critical To Bleed The Air Out Of An Injection ?
You probably do not need to do anything about it, if there is no unusual activity at the injection site. Air bubble can be a problem with the 'intravenous' injections (embolism threat), but not so with the intramuscular injection. The air would probably be absorbed in the tissue in some time. If the amount of the air was too large, it might lead to pressure symptoms within the tissue, such as dissection, but it won't create clinically significant problems.
I hope this helps. Hope your wife's medication course is successful. Let me know if you have more thoughts to discuss. I will be glad to help.
Abhijeet Deshmukh, MD