it seems like after the first few levels the usefulness of poisons dramatically fall off. Most poisons only have a DC 10-13 con saving throw .... so by level 5 or 6 most enemy creatures are more often the not making saving throw. Are we not understanding the rules of poison correctly ? does the poisoner's kit proficiency have anything to do with the potency of of the product? 

The same argument could be made for Warhorses. With an AC of 11 and 19hp they will not last long on in a CR 5 or 6 encounter.

But actually....is it just  the combat usefulness that drops. The Warhorse will still get you to where you need to be, and that low level poison will still kill the run of the mill citizen or noble. It can quietly take out the baron's prized wolfhound guard dogs or cripple a castle's defenses. Even at higher level (especially in 5th E) there are still a lot of lower level types who are susceptible to poison or a good trampling. 

The longer a creature is likely to last in combat though, the more detrimental the poisoned condition is....

One way to view the saving throw against poison is to assume all poisons are relatively deadly effective, and the chances of surviving a poisoned wound/drink/gas is minimal. The D20+proficiency throw reflects the chance of the attack not actually being affected (dodged the blow and HP loss is bruising/distracting/tiring only, or the imbiber notices a faint chemical smell and refuses to eat or enter the area of the gas.) Additional bonuses such as from Con or Dwarven heritage etc, reflects a small amount of the poison being introduced, but not enough to affect the victim.

I'm sure many DMs will allow upgraded poisons (and upgraded costs), but mostly, as far as combat goes, poisons do seem weaker - but you can afford to use them more, and when they are effective, they can be more effective.

A 5th level fighter shooting twice a round means that a creature that would fail to save 40% of the time, now will fail to save 64% of the time.... hmmm, maybe not that much weaker after all?

Statistics - You can 'prove' almost anything.

 Edited as my statistic were pre-lunch, and therefore wrong. Fixed now. I think.

I just feel like poison need to have some kind of scaler factor .... as one becomes better at making poisons one would expect to make deadlier versions of even simple poisons .... the process should be more similar to like the magic saves I guess .... something like 8 + the poison type + proficiency bonus or something .... 

 It's not just that you get better at making poisons, but that you also get better at administering them.

 Poison Spray doubles in damage from 4th to 5th level and has a -1 penalty to saves against it. From 3rd to 4th level it may get an additional -1 if the ASI is taken in the appropriate stat. 
 Does this extra potency come from a greater volume of poison, better concentration of poison, improved technique for dowsing the victim in it, or a combination of these three and other factors?

I don't think that what you are asking for is unreasonable. I do think there would be consequences. I also think most of those consequences would be worse for the PCs, depending on how competitive/realistic/vindictive the DM is.  /Evil Grin.  :)

 i mean look at a Young Green Dragon (CR 8) its poison breath has a Con save of 14 or does 42 points of damage (21 if saved) .... I would rather see it like have a 18 Con save and then take 1d8 poison damage a turn for 10 turns ... in my opinion these lasting injuries would totally change the dynamic of the fight .... as the dragon slowly fills the field with poison gas it forces the players to fight more tactically ... in my mind at least. 

A lot of poison in combat has become flavor over mechanic, which is unfortunate. As has been pointed out it is simple enough to make small changes to the way poison scales without breaking the game, the key is small changes.

A player chooses to grab an alchemist or herbalist's kit, the player can become more familiar with what plants and materials are needed to make a more effective poison. So you decide to allow them to roll on a table, or give them the choice of increasing the DC or damage of the poison. At certain levels, perhaps following the class progression theme, 3, 6, 14, each one allows the poisons to go up in either DC or damage. You could simply base it off of proficiency, since that scales at a good rate, and have them choose in an either/or way for DC or damage as the bonus to the poison. The trick is they can only gain the benefit from the alchemist's kit or the herbalist's kit, not both. 

I give you permission to use this rule in your own games.  :D

But...........A Con Save DC of 18 for a level 8 character means a 30% chance to save, +5% for each point of Con bonus. That is quite harsh. If you stick with that, maybe a free save whenever you start a turn in clear air?

But again, if the players know that they are almost definitely going to take damage, then they will have to plan for that. They probably won't be happy about it though!
Gust of Wind would suddenly become a more popular spell!

i like the idea of making poison less all or nothing and instead shaving away HP over a period of time .... small amounts of damage would have all kinds havoc on the battle field ... think about the concentration checks every turn to maintain concentration spells on every turn... it would also cause the players to flee a particular part of the battle field ... I'm thinking about using systems similar to Spell casting saves to act as poison saves.  do you think this would break the game ? 

"think about the concentration checks every turn to maintain concentration spells on every turn..."

I confess that hadn't occurred to me - you sir, are an evil genius!

"do you think this would break the game ? "   The game is unbreakable. It can be changed - for better or worse - but not broken. Well, not easily.

"One does not simply break D&D." - Boromir.

It would probably make it more like 4th Edition though.....for better or for worse. 

I normally homebrew a lot of stuff like that. If my character is proficient with Alchemist's supplies, I've got a sheet typed up with all the stuff he can make, how much the supplies cost, how long it takes to create, and the same goes for poisoner's kit. In the case of poisoner's kit, I do what someone mentioned up there (8 + your int modifier + your proficiency bonus) is the poison save.

i wish that each tool skill had been officially assigned a corresponding attribute skill. For example, Disguise kit would be charisma (how convincing you are as a fake whatever) Alchemist kit would be intelligence (knowing how things react) and cooking kits could be wisdom, Wood carving kit would be dex ...etc... this would make all kinds of calculations much much easier. 

Does anyone know if there is a similar list from past versions or what not? 

Quote from The_Plundered_Tombs>>

The same argument could be made for Warhorses. With an AC of 11 and 19hp they will not last long on in a CR 5 or 6 encounter.

There's easy solutions to keeping a warhorse alive. Aid and/or Warding Bond will go a long way towards reducing the chances of dropping to 0 in one damage roll. The Mounted Combatant feat lets you redirect all attacks to yourself and effectively gives it Evasion. Commanding it to use the Dodge action doesn't cost you your own action and increases the chances of succeeding on DEX saves.

Anyways, the thing about poisons is that they literally let you trade money for more combat effectiveness. That's something that has to be very carefully controlled, or you have to build the game around the assumption that everyone's getting extra damage from poison all the time. No matter how high level you get, it's still free damage, and at higher levels you can afford more of it and thus use it more liberally. Also, I disagree that by level 5 or 6 most monsters will make the save. Monsters rarely have saving throw proficiencies and CON correlates well with size, so you can predict which ones will be harder to poison, and you'll be hard-pressed to find CON mods of +5 on monsters that aren't Huge or legendary creatures. Bane is also a fairly accessible way to nerf saving throws.

I think poison works great in D&D if you're an NPC.
NPC's have great and interesting poisons.  Some of them deal poison damage others acid damage, they increase in effectiveness with level.

As for fixing it?
I think if you want to make a Rogue that's a poison maker use the Arcane Trickster/Battlemaster/Hunter/Divine Smite as a baseline.
Have them be abilities that they use either per short-rest or per long-rest.

The problem with poison being an equipment is that it's not "balanced" vs class features, which is why it's awesome on Monsters because it's built into their CR.
If you look to the per *-rest, and it'll be easier to tinker and tweek them vs either as creating spells in the DMG or abilities like the Battle Master or Ranger's Hunter to deal extra damage.

i feel like if you were going to make a poisoner sub class ... it should be a ranger sub class ... perhaps even treating them like spells augmenting (or replacing) the already very limited ranger spell set. 

Quote from Cporter5 >>

i feel like if you were going to make a poisoner sub class ... it should be a ranger sub class ... perhaps even treating them like spells augmenting (or replacing) the already very limited ranger spell set. 

I actually really like this idea.

because then you could simply use the spell save mechanics (dex, con, wis) as the ability to resist the poison and its easy to scale poison potency. A level 5 poison is obviously stronger than a level 1 poison. It would also allow a simple poison to be brewed at a stronger concentration (casting a level 1 spell at level 5.)

The only mechanic change would be making a ranger a "Prepared" spell caster instead of a learned. So you may know 15 different poison recipes but only have 4 prepared. Finally, the Poisoner's kit would act like the Arcane Focus for this ability set. 

Thoughts? 

I think it should be doable to make a "poisoner" subclass for really Fighter/Ranger/Rogue.
I personally would see it as Rogue first, but one thing I like about 5th Ed is the flexibility.

It would be easy to make a "Ranger" out of a Fighter by taking the Eldtrich Knight and giving it Druid spells.  It wouldn't be exactly the same as a Ranger, but it would be very close.

I like your thoughts Cporter5, I think it would make a very "Witcher" style sub-class.

The mechanics already kind of make sense its really just some new spells and flavor. For example a level 7 "Poisoner" would have the skills to brew 4 potions of level 1 potency and 3 potions of level 2 potency during a long rest. I think the blowgun could be an interesting low level weapon for the class, as it would basically be a poison delivery system. Maybe even worthy of doing something like the monks unarmed combat where as levels increase it does more and more damage.  This would allow the Poisoner to effect a single target at distance (Making a ranged attack.) Perhaps at a higher level 11 they would learn how to use the Sling weapon to throw an entire bottle of poison (vs coating a weapon or ammunition) which would be an area of effect style system requiring groups of targets to make saving throws (more like fireball) 

Thoughts? 

Standard poisons that players can make? Yeah, sadly so. The more exotic poisons that players can buy? Those are useful if you know how to get ahold of them.

The funny thing about poisons is that they basically come off as magical potions that you apply, or throw, or whatever. They have set DC, they have set abilities, they have set damage. Little different than tossing an exploding potion of fireball. So, they're actually pretty consistent with how other items work in the game.

Granted, the extra damage that require a save or no damage is a bit strange, considering that you also have to make a hit with a weapon - you should either do the damage on a hit, or you should have a save DC against something with a sleep/paralysis/etc effect. 

I'm all for a poison themed rogue subclass.  Its like those stories about people raised on poison so that their entire bodies are poison - their blood, their spit, etc are all deadly. Perfect fantasy archetype. I'd do it in the same form as Arcane Archer, probably (I strongly dislike the 1/3 caster style used by eldritch knight, arcane  trickster and elemental monk).