Ratio of Binder to Active Ingredient

[nikol]

In a completely hypothetical situation, someone is trying to press mescaline into a pill. How is it determined what ratio of binder is necessary to hold a solid pill shape? (This really is hypothetical, I'm using a very simple example because I am actually trying to figure out how large/how much a mescaline pill would be/weigh if it was indeed only mescaline and enough binder to give it shape).
I'm assuming that different substances are going to require different ratios of binder to hold them into a pill shape. I'm also assuming that chemists and people with similar interests know the rules behind how to determine what amounts of what are necessary. So... what are those rules? Is there some way that you can figure it out using technical/chemical knowledge of the substances involved, or is it something extraordinarily complex to figure out and is instead the kind of knowledge that gets passed around, because once it's been determined it doesn't ever change?
Essentially I'm trying to compile a list for myself of (in hypothetical situations) how large a pill would have to be/how much it would have to weigh to contain an active dose of "xyz" + binder.

 

[vecktor]

In a completely hypothetical situation, someone is trying to press mescaline into a pill. How is it determined what ratio of binder is necessary to hold a solid pill shape? (This really is hypothetical, I'm using a very simple example because I am actually trying to figure out how large/how much a mescaline pill would be/weigh if it was indeed only mescaline and enough binder to give it shape).
I'm assuming that different substances are going to require different ratios of binder to hold them into a pill shape. I'm also assuming that chemists and people with similar interests know the rules behind how to determine what amounts of what are necessary. So... what are those rules? Is there some way that you can figure it out using technical/chemical knowledge of the substances involved, or is it something extraordinarily complex to figure out and is instead the kind of knowledge that gets passed around, because once it's been determined it doesn't ever change?

it depends on many things, what the excipient is (the bulking agent) whether there are flow modifiers, how dry something is, whether the API is finely ground or in crystaline form. how much pressure can be applied etc.

there are not so much empirical rules as guidelines and then the formulation development guys experiment around until they get a formulation that breaks up when needed but not before, and is as cheap and stable as possible.
on the whole pharmaceutical makers do not just use a binder and active ingredient, because most actives are too uneven sized and are difficult to press alone.
Assuming that mescaline pills contained 300mg of hydrochloride or 400mg of sulphate they would have dimensions similar to a 500mg paracetamol tablet, perhaps a little smaller and would weigh 500-800 mg. Nowadays most 'mescaline pills' are just whatever cheap RC is around, in the olden days it used to be LSD, but this is getting less common.

 

[Ham-milton]

I think that for 300-400mg of active material you'd need AT LEAST 800mg of inactive junk. APAP is a little different since it seems to press easier into a pill with fewer junk than I think you'd need for mescaline hydrochloride powder.

When you're a major pharmaceutical company, it's pretty important.

But for someone just wanting to press some decent tablets that'd hold up decently? It won't be nearly that difficult.

I'd look at the ingredient lists for other similar substances of similar potency. I think it's going to be substantially different for a pill you want to contain 40mg vs 500mg of active material (even adjusted for pill size). It seems like something that won't scale well.

 

[nikol]

I'm aware that generally there isn't actually mescaline pressed into pills- it was actually a claim from a friend that he knew pills that were in fact made of mescaline that prompted this question.

on the whole pharmaceutical makers do not just use a binder and active ingredient, because most actives are too uneven sized and are difficult to press alone.

Is something used... in place of the active ingredient, then? Or are you saying that this is where other inert compounds are going to come into play? If so, does this mean that for the most part pretty much anything pressed into a pill shape is going to contain active ingredient (or whatever) + some form of binder + inert substances for stability? I think that is what you are saying but forgive me if I am way off.

But for someone just wanting to press some decent tablets that'd hold up decently? It won't be nearly that difficult.

If I am correct in my previous assumption about pills needing (as a general rule) something other than just binder + active for stability, then does this imply that pills made without quality control may be lacking in those things... that possibly those kinds of black market pills would indeed be closer to the active + binder model as opposed to active + binder + stabilifying agent/filler.

I'd look at the ingredient lists for other similar substances of similar potency. I think it's going to be substantially different for a pill you want to contain 40mg vs 500mg of active material (even adjusted for pill size). It seems like something that won't scale well.

Right, it makes sense that there would be an upper limit as to how much of one thing can stable as a pill without it losing the ability to hold shape. Does more than one kind of binder exist, and if so, is it safe to assume that all of them are going to have their own properties that effect... essentially, how well they bind to different things at different amounts?

Again, forgive, I most definitely did not excel in chemistry in school.

 

[MattPsy]

Depending on the characteristics of the API (active pharmaceutical ingredient) you're pressing, you can make do with as little as 10% w/w of the pill as binder. Yes, different binders will suit different APIs. There are many different binders.
Yes black market pills will likely have formulations which require higher proportions of binder since they will be less likely to be using high performance binders, and they may be missing flow modifiers, compression aids, etc. Also, the presses they will be using are probably able to exert less pressure, so having more binder means their pills are less likely to crumble.

 

[johanneschimpo]

Your friend doesn't really have mescaline pills. Sorry to break your heart.

 

[nikol]

Your friend doesn't really have mescaline pills. Sorry to break your heart.

I know that, I never assumed that he did. I'm not an idiot. That's why I made it very clear that this was a hypothetical situation. Given how often people toss around that claim I figured it would be an easy starting point for setting up a simple model of various pill situations. Next time try contributing something to my OP, thanks.

Depending on the characteristics of the API (active pharmaceutical ingredient) you're pressing

This is closing in the closest on what I am trying to figure out. What characteristics of the API are used to determine what binders/everything else will be necessary? Are there different characteristics for each API that have to be individually determined, or is there some standardized way of determining them? This is kind of confusing for me, so to make sure I'm actually asking the question I think I am, please consider this brief, very simplified example:

Say chemical R has the attributes of a, b, and c. All of these somehow equal x. X is the formula/ingredients list/necessary ratios of the final pressed pill. The question is: are a, b, and c all objective attributes of chemical R (that is, are they something that every chemical has as an indentifying characteric but is something that will be of a different value for each chemical) that do not change (as in, the same variables will always plug into the same parts of the equation to acheive x? Or are a, b, and c going to be different attributes each time as they are dependant upon the API to determine which objective attributes are used as a, b, and c and in what order or fashion.
Essentially, is x dependant on a, b, and c as they are, every time, or is it going to be depedant on the API to set the limits for a, b, and c?

 

[vecktor]

^ you are after the impossible, if there was a ratio or a formula which could be calculated, then all the formulation guys would be put out of a job, there are general rules followed by trial and error this is done early on in a drugs career. once a formulation is settled upon it is then stuck to because that is the approved form of a drug.
Most tabletted drugs have 1, active ingredient, 2- bulking agent, 3- flow modifier, 4 binding agent. they may also include agents that help disintegration or slow disintegration, agents that protect the API, buffers, chelating agents god knows what else. there is a trend t produce tablets now with as much api as possible because geriatrics and others find large pills difficult. in the very best examples the API is 90% of the total tablet weight.

so general rule is that mescaline pills containing say 300mg of HCl or 400mg of sulphate will weigh 500 to 800mg and perhaps be 11mm by 4-6 mm, or they could weigh 2.5 kilos and be 20cm across and 5cm deep.

 

[ghost1231]

what is the ration of binders and bulkers and what are the commonly used products for e,s