If your organization is having formulation changes then those would need to be reported, stability reconfirmed, and process method revalidated. That’s just the rules.
As @Lincoln20XX said - there are tolerance limits, your company defines what those are, as long as they are within the legal limits set by HC.
You could be pushing higher, this happens often due to environmental changes without intentionally changing the formulation. What you are describing doesn’t really sound like that though.
Do you know why the average weight is changing? Is it changing more than the formulation defined percentage? That percentage of tolerance should be on your batch record and part of your quality control review process. Someone should be checking them every so often just to make sure all is correct.
Its possible that your quality control department knows this is an issue and is already investigating it and working on a corrective action. This kind of stuff happens.
If you don’t have a QC department, then it will be much harder to meet HCs demands. I’m pretty sure they actually require you have one. Sometimes people have them, but don’t really fund them so its hard for them to do their work.
In any case - when you submit your product for consideration that includes the formulation, which includes all ingredients, quantities, unit weights, tolerances, and dosing information. This gets approved. Its a pretty simple process.
As chemists its totally normal for us to feel weird when things are kind of back of the napkin mathematics. Just try to remember that is how it is for ALL FOODS and most DRUGS. Tolerances for all ingredients, averages instead of actuals.
I don’t know which lab you are using (are you doing the testing yourself?) – in all of my labs we ask that we get enough units to do a 10 piece average weight. If the RSD across those is less than 2% then we call it “good” and move forward with the average weight of those items. In some labs, we let this number remain consistent across many months of testing - unless there is a laboratory investigation.
Sadly - many states (although I don’t think HC…) don’t require that you submit enough “samples” for you to really get a good representative sample. That means that these numbers are all bogus most the time anyway. And with limited process validation - you could be pushing out all kinds of stuff.
This has always made me uncomfortable as well - because I come from pharma under the FDA where the regulations require that you CARE about these things and MONITOR/CONTROL for them.
Food is just not the same and most states and HC seems to lean towards treating cannabis products like food and not like dietary supplements or drugs.
Such is life. Feel free to reach out if you want to talk about it a bit more. There are methods to do some more checks, and it may not be nearly as bad as it seems.
Oh and remember - you may be thinking that a calculated potency of a dosage form is inappropriate because it feels like it has too much error built, but there is always uncertainty - and how much we are willing to accept is all up to our risk tolerance. And most people think the risk with cannabis products is pretty low (its not like hormones… or opiates… where dosage shifts will kill you…) so perhaps you can take a nice exhale knowing that even if there is something wrong with the math, it probably isn’t so wrong that it will kill someone, but instead just get you in trouble with the regulators if they decide to look at it, which they probably won’t. <3 -hugs from Michigan, which I’m told is basically Canada-