Saline flush..saline taste?

[Gabriel13]

I'm sure many of you are aware of this phenomenon. When you go to flush your patient's IV lock, with say...a 10cc pre-filled syringe of normal saline, they experience this taste or sometimes a smell. I've heard it described as "metallic" or "salty." Can anyone out there explain to me the physiology of how this happens?

[jlr820]

Hi,

I don't know the exact cause for this phenomenon (either with certain drugs, like Flagyl, or saline flush) but what I've heard is that the involved substance alters the taste receptors and/or the chemical composition of saliva and that's why the patient perceives a change in taste. I haven't encountered a patient that had a change in smell, so I'm not sure on that one. However, it seems reasonable to assume that a medication could also cause changes in smell receptors in the nose (but I don't know that with certainty). Again, there's likely more to it than that, but it's what I've been told. :)

[PAERRN20]

I have often wondered this too. I hear it most often with a flush. Oddly enough I have never heard anyone complain when I let a bag of saline free flow. But it is almost a daily occurrence when I push saline they get the salty/metallic taste though.

[Gabriel13]

Yes!! And the effect is immediate! Within 2-4 seconds of pushing the saline flush they get that taste and/or smell.

[Larry77, RN]

I let a couple students practice on me one day and made sure they flushed with 10ml NS to see if I could "taste" it and I couldn't tell at all...but yes I've heard this many, many times.

[mamamerlee, LPN]

I don't know why it happens with flushes and not drips, but it has to do with the anatomy of the circulatory system, and the proximity of blood vessels to the tongue and taste buds. There are many IV meds that have taste, and why only a small percentage of people can taste them is a 'puzzlement'.

Many of my dialysis patients complained about the saline in the lines, about certain types of heparin, about Mannitol, etc.

[PostOpPrincess, BSN, RN]

Interesting.

Never heard or seen it.

Thanks for info.

[Lacie, BSN, RN]

I have one patient who sleeps his entire dialysis treatment so when I push his Zemplar it always wakes him up with an extremely comical look on his face. You can tell it obviously is a nasty perception to him then he'll look at me and laugh!! Also when we give Hypertonic saline pushes they also get a very salty taste in thier mouth. I think I see more reaction from Zemplar than anything I have given. Takes about 2 seconds.

[Kyrshamarks, BSN, RN]

I always taste the saline flushes when ever I have had them. I thin it is more a chemical taste than anything. I had a PICC line for 2 months and hated the flushes and i was getting 2 different ABX for a total of 5 times a day.....lots of flushes used.

[RN <><]

In my personal experience I have tasted and smelled the saline flush, but it did not bother me...I just thought it was cool. :nuke: Good question, I wonder myself.

[RN_ReFlux]

In the facility that I work in, patient's began complaining of the metallic or salty taste after flushing when we began using pre-filled flush syringes. Prior to that, we had to draw our own flush up from 5-10 ml bottles.

[LilgirlRN, ADN, RN]

I can tell you from personal experience that there is a chemical taste with NS flushes. Toradol tastes sweet. Why this is, I dunno.