My first injection was lumpy and very very painful. I though I must be doing something wrong, and after doing a lot of reserach found that I was: I injected a too-cold paste, too quickly into a tense muscle.
Here's how I got rid of injection-lumps since then; this worked for me, and resulted in painless injections, but might not work for everyone:
1) Take Bicillin IM out of fridge at least an hour before injecting to let it warm up to room temperature. (I do mine just before bedtime, as my body will be most relaxed thereafter, for at least 8 hours during the night.)
2) 5 minutes before injecting, hold injection (suspension part) closed in fist grip in palm of hand to let the thick liquid warm to body temperature (with cap and not needle still on), while keeping the injection in a vertical position, and shaking it up and down a few times and hitting my closed fist with my other hand to cause impact shock in order to shake the pasty substance into a less viscous state. Do this for at least 5 minutes.
3) Inject in upper thigh in stead of hip, rotating legs. (Don't forget to first swab injection area in circle movement from inner to outer ring with alcohol swab.) Use a different spot to inject into each time.
4) Let legg hang loose, foot only slightly touching ground, while relaxing all muscles as much as possible.
5) Just prior to injecting, use fingers to shake thigh muscle from side to side a bit to further relax the muscle.
6) Push the 2" needle (not shorter - especially for bigger folks) in all the way, to get deep down into the muscle and avoid injecting into fatty or dermis layers, using the z-track method (google this, it helps with leakage, by sealing off the "hole.") (Remember to first pull back on the injection plunger for 10-20 seconds - aspirating - after inserting it, prior to pushing out the liquid, to check that you are not injecting into a vein or artery or blood vessel. If you had, blood will show in tube. Release needle, remove, and start over.)
7) Inject very very slowly with an even motion (20 sec at least). Take your time.
8) After all liquid has been injected, hold the needle in, still, for 10-20 seconds, then pull out slowly, while keeping other hand ready with sterile alcohol swab.
9) Immediately upon removing the needle, press firmly down on the puncture mark with alcohol swab, and hold it there for at least a minute.
10) Then replace the swab with a plaster / band-aid, but continue to lightly press down on the injection site for another minute or so.
11) Walk around in a normal fashion for a while (as long as you want to or can stand to, then go lie down to sleep.
Using these tecniques, I , consequently, have painfree and lumpfree injections.
I hope this helps somebody. I will re-post this with an earlier post about Bicillin on Facebook, as well as here on my blog so everyone can access the info.
Additional info:
http://www.drugs.com/cg/how-to-give-an-intramuscular-injection.html
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