Medical Dumps for Writers: Injections
Updated: Mar 15

As a combat medic for the Marine Corps, I have gone through way too many trauma courses and medical courses. I love the random tidbits of medical information I have learned throughout the years, and this means I’m able to share it with writers who are including some medical aspects in their work. Please keep in mind that I am not a licensed medical professional, you should not do this to anyone in real life, and this article was written explicitly for fiction writers in fictional works.
Injections are one of the big things I see written wrong a lot. Patients get injections in the neck and immediately pass out, and that’s frustrating and not realistic. Here are the two most common ways of injecting medication into your fictional patients.
Intramuscular (IM) injections go into the muscles of your patient. This is typically for antibiotic use, pain relievers, and some sedatives. While most injections can go into the upper arm (think where you get your flu shot!), bigger doses need to be given in a bigger muscle mass—that’s the glutes, baby. IM medications take time to kick in and are not instantaneous. Some IM medications will leave the injected muscle tissue sore.
Sedatives: take 10-15 minutes to kick in
Pain medications: take 30 minutes to kick in
Antibiotic use: can be 1 dose and done, can require multiple doses spread throughout days/weeks
Intravenous (IV) injections go into the veins of your patient. The vein typically used is in the antecubital space of the arm—the inside of your elbow. Other areas include the back of the hand or the bulging vein on the inside of the wrist by the thumb, but unless you have a specific reason why the antecubital space can’t be used, just use it. Typically, a patient would have an IV saline lock placed already. The medication can either be injected via syringe through the saline lock, or diluted through an entire saline bag. The reason a saline lock is placed prior to any drug injection is because of the possibility of missing the vein altogether and injecting medication elsewhere. IV saline bags are used to provide hydration to patients. Saline is a clear liquid and has sodium chloride in it to raise the salt content of the patient.
Sedatives: take 20 seconds to kick in
Pain medication: takes 15-20 seconds to kick in if injected all at once; sometimes they will dilute it over time through a saline bag
Antibiotic use: diluted through a saline bag, might require more than one dose
Please stop injecting your characters in the neck. Have you ever been injected into the neck? I didn’t think so. It’s a terrible artery to try to hit, and if you miss it, you get tendons or even worse, the throat. And the likelihood of you getting an injection into the neck artery of a struggling victim is actually zero. Patients who rip out their IVs also need to perform immediate aftercare, such as stopping the bleeding from their arm. It also hurts.
Medical information is one of the hardest things to get right and one of the easiest ways to piss off a reader when you get it wrong. By using more realistic facts in your work, you can keep your readers in the story instead of focusing on the incorrect details.
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