Author Question: How Fast Does A Tranquilizer Dart Work?

Alyson Asks:

I’m writing a script where the villains shoot people with a gun but we discover later it was only a tranquilizer. Is there a tranquilizer drug combination that can be shot from a distance (can be close range) at a person that would take effect fairly immediately? Or would stop them from being able to communicate immediately.

Jordyn Says:

Thanks for sending me your question.

There is no drug combination given intramuscularly (IM or within the muscle as a dart injection would be) that would incapacitate a victim immediately or even within a few seconds. For instance, Ketamine takes 3-4 minutes to work IM. This will be the case with most drugs given via this route— the range of 2-4 minutes for onset of action.

Hope this answers your question.

Best of luck with your story.

Author Question: Drug Injection Scene

Kiri Asks:

I really hope you can help me. I feel like I’ve reached out to half the medical community and still haven’t gotten an answer.

I have a protagonist who suffered a ruptured aneurysm two years before the story starts. The aneurysm caused a stroke. Presently, he is mostly recovered, though he still suffers migraines and some memory loss. I have a scene where another character catches sight of yet another character giving my protagonist a shot in the arm.

Originally, I had the intramuscular injection be a vasopressor to help with his blood pressure, but then someone told me this would only be done in a hospital.

I would really like to keep this injection scene. So I changed it to an anticoagulant, though I’m having trouble verifying that this is anything someone like him might need. (Did I mention he has another blood vessel wall bulging and ready to burst, this one inoperable?)

I also have him taking beta blockers for his migraines and he later uses these to try to commit suicide by taking an entire bottle. An ER nurse told me this would certainly be dangerous. I could change it to another drug.

Any thoughts are much appreciated.

Jordyn Says:

First of all, you have two competing medications. A vasopressor raises blood pressure and are typically given IV in the ER and ICU setting. The beta blocker used for his migraines can (and often does) lower blood pressure.

Unfortunately, I don’t see either of your two options as feasible for an intramuscular injection scene— either as an anticoagulant or a blood pressure medication. If the character’s blood pressure is too low, the first thing would likely be to give him some IV fluids and just stop the beta blocker.

Some patients do go home on subcutaneous (SQ) anticoagulant therapy, but usually it’s when they have a known clot— not simply to just keep the blood thin. There are too many excellent prescribed oral medications to do this on an outpatient basis. If you wanted your patient to have a clot in the leg (deep vein thrombosis) than this therapy would be reasonable but developing a clot like this would be unlikely if he were already on anticoagulants for his brain coils related to treatment of his first aneurysm. You could read more about this here.

I’m not aware of any blood pressure medicines that are given SQ or IM (into the muscle). There are several given IV in the emergency/ICU setting but these would not be appropriate for home use. Patients are transitioned to home oral medications.

The only medication that could be given consistently SQ on a home basis with any regularity that I could see would be insulin for diabetes.

I did find this pamphlet on-line about SQ meds given in palliative care (hospice) but I don’t think any would fit your scenario. They are mostly anti-anxiety, anti-nausea, or drying agents for secretions given this way because the patient can’t swallow anymore. In fact, most of the links about SQ meds given at home were in conjuction with hospice care.

Also, SQ and IM sites and the angle at which they are given are different as well.

Probably best to find an alternative to this scene.