# Nitro Expiration After Opening Bottle?



## 18G

What is the recommended expiration of sublingual nitroglycerin after opening? I was told the bottle should be discarded after every use which I have never heard of before. I have only seen discard 6mo after opening at the earliest and have also read that with new formulations nitro is stable for the entire expiration date after opening?

Does anyone have any sources to support either positions?


----------



## 46Young

http://www.prairiecardiovascular.com/Forms from Theresa/Nitroglycerine.pdf

http://www.ask-curtis.com/how-stable-are-nitroglycerin-tablets-after-being-opened/

Six months after opening the bottle, according to these guys

I checked the insert labels on this site, but I saw no mention of the 30 min. rule:

http://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=79BA021E-183C-4B4D-822E-4FF5EF54CA61


----------



## 18G

I found this Pharmacist Newsletter that provides some pretty specific info on the question...

June 2003


"Tablet Stability

Past tradition has led pharmacists to counsel patients on the “instability” of sublingual nitroglycerin (Nitrostat, NitroQuick, NitroTab). We told patients that SL NTG was easily degraded by air, moisture, and light. We told them to frequently replace opened bottles (usually every six months). Is this information correct today? No, this is NOT true today. NTG tablets have been reformulated to a stabilized formulation. These are compressed tablets; the old tablets were molded. Expiration date from the time of manufacture is 24 months.

Long-term testing (greater than 24 months) of the tablets has demonstrated excellent physical and chemical properties when exposed to continuous daily opening and closing of the container. Testing was accomplished with exposure to recommended room temperatures and humidity.1,2 It is currently recommended that patients keep the NTG in the original glass container, tightly capped. Store the tablets at room temperature, 20 ̊ to 25 ̊ C (68 ̊ to 77 ̊ F).3,4 Patients should use the tablets until the labeled expiration date is reached. The original NTG container should be used and tightly resealed after each use. Tablets are expected to retain full- labeled potency when stored under recommended conditions, even with frequent opening.1,2

Potency

Due to NTG tablet reformulation and greater stability, the newer tablets may take ten to 20 seconds longer to dissolve in the mouth. Vasodilatory effects occur approximately one to three minutes following a sublingual dose. A maximum effect is reached within five minutes after a dose, with effects lasting for at least 25 minutes.3

A burning or tingling sensation sometimes occurs following sublingual dosing. The stabilized formulation of NTG may be less likely

to produce this effect, and some patients are less sensitive to this. The burning/tingling sensation should not be used as an indicator of tablet potency.2,3,4"

ftp://host-208-105-2-96.midco.net/Seagate_Expansion_Drive/Karla%20PC%20C%20drive/NP%20School/NUR%20568/Cardio/Sublingual_NTG_and_Stability_Prescribers_Letter_20.pdf

And this...

The physical stability of one type of stabilized molded and three types of compressed nitroglycerin tablets was studied. The evaporation rate of nitroglycerin was controlled by its vapour pressure and by the matrix effect of the dosage forms. The four products showed different vapour pressures and matrix effects. In time nitroglycerin escapes from the outmost layers of the tablets; the dosage form in which the drug showed the lowest vapour pressure (the stabilized molded tablet) was found to be the most stable one. However, from the time when the drug had escaped from the outmost layers of the dosage form, the matrix effect became dominant. *When nitroglycerin tablets were stored in tightly closed containers at room temperature potency loss was minimal. Even when the bottles were opened regularly this did not result in a significant loss of the drug.* Measures are suggested to minimize drug evaporation.

http://www.ncbi.nlm.nih.gov/pubmed/3145487


----------



## 18G

46Young... what the the policy at your agency? Or do you use nitro spray?


----------



## cprted

We discard bottles of SL nitro after each patient.  Think about how close to your patient's mouth the bottle is when you administer it ...


----------



## 18G

I'm referring to nitro tabs, not the spray.


----------



## 18G

cprted said:


> We discard bottles of SL nitro after each patient.  Think about how close to your patient's mouth the bottle is when you administer it ...



Here in the U.S. nitro spray is like $200 a bottle. I've not seen an ALS agency throw a whole bottle of nitro spray away after say two doses.


----------



## cprted

18G said:


> Here in the U.S. nitro spray is like $200 a bottle. I've not seen an ALS agency throw a whole bottle of nitro spray away after say two doses.


$200?  Those must be some massive bottles.  Ours have 75x0.4mg sprays ... cost is about $12-15 a piece.


----------



## 18G

cprted said:


> $200?  Those must be some massive bottles.  Ours have 75x0.4mg sprays ... cost is about $12-15 a piece.



Nope... just regular sized bottles with 60 to 200 metered doses.


https://www.mooremedical.com/index....G=CTL&CS=HOM&FN=ProductDetail&PID=22210&spx=1

http://www.buyemp.com/product/nitromist-aerosol-delivery-system?exactMatch=1&sSearch=nitro+spray


----------



## cprted

18G said:


> Nope... just regular sized bottles with 60 to 200 metered doses.
> 
> 
> https://www.mooremedical.com/index....G=CTL&CS=HOM&FN=ProductDetail&PID=22210&spx=1
> 
> http://www.buyemp.com/product/nitromist-aerosol-delivery-system?exactMatch=1&sSearch=nitro+spray


That's insane!


----------



## chaz90

Huh. Interesting links above. I already knew glucagon and Narcan were pricey, but the Cyanokit was quite a surprise. It's crazy to see how much it takes to stock each of our drug boxes, even if the prices vary some for bulk or facility orders.


----------



## Carlos Danger

18G said:


> Does anyone have any sources to support either positions?



With any drug, you have to look at the recommendations from the manufacturer of the specific brand drug you are using. The same drug can have different recommendations from different manufacturers.


----------



## TransportJockey

A buddy of mine who runs an EMS page on Facebook emailed Pfizer to ask. They said if stored within the bottle it comes in, the tabs should be good until the expiration datw


----------



## zzyzx

"We discard bottles of SL nitro after each patient. Think about how close to your patient's mouth the bottle is when you administer it ..."

Ours cost $75 - 100, so your agency must be getting an incredible deal if you get them for $15. That still seems like an awful waste though. If you're worried about infection, why not just wipe it down?


----------



## triemal04

zzyzx said:


> "We discard bottles of SL nitro after each patient. Think about how close to your patient's mouth the bottle is when you administer it ..."
> 
> Ours cost $75 - 100, so your agency must be getting an incredible deal if you get them for $15. That still seems like an awful waste though. If you're worried about infection, why not just wipe it down?


Pssst!  He's from Canada!


----------



## YoungMedic

Protocol here is if we use Spray, its a single pt use only.  If tablets are broke open and used, we date it for 30 days from opened.  After 30 days its expired.


----------



## NomadicMedic

In DE, we were not allowed to use NTG spray with multiple patients because a PharmD in the state read an article stating there *may* be an infection control issue with the bottle aspirating air containing infectious material after administering a sprayed dose. And this PharmD had the ear of the medical directors...

So, we had to stay with tabs. 

However, Boundtree carries a non aspirating spray NTG kit. It's always primed and ready to go. Downside? It's very expensive. 

So, we had to stay with tabs. 

And we tossed them every 30 days. Along with all of our unused succinylcholine and Cardizem.


----------



## WolfmanHarris

triemal04 said:


> Pssst!  He's from Canada!



My service pays under a dollar per NTG spray. I was discussing it with a Sup and we were trying to figure out how you can even make a glass bottle and pump that sells that cheap even before the drug is added.


----------

