A Guide to D&D 5e’s Rules on Suffocation & Holding Breath

The dangers of being an adventurer in Dungeons & Dragons 5^th Edition are numerous and often magical. But, sometimes the more mundane dangers are some of the most frightening for player characters. One such danger is the threat of suffocation since there are few ways around it in 5e.
 
What are the rules on suffocation in D&D 5e? How long can a creature hold its breath? And, how and why would a Game Master use suffocation in an encounter?
 

Let’s start by looking at the explicit rules for suffocating in the Player’s Handbook.

Rules on Suffocation in 5e

D&D 5e includes specific rules on suffocation which involve a creature falling to 0 hit points and dying. These rules are not instant death sentences as there are stages to suffocating in 5e, but the danger of dying is very real.

5e’s rules for suffocation come from Chapter 8: Adventuring of the Player’s Handbook:

We’ll get into how long a creature can hold its breath in the next section. So, let’s look at how suffocating works in 5e.

First off, once a creature runs out of breath or starts choking (i.e., some hostile entity is actively strangling that creature), they maintain consciousness for a number of rounds equal to their Constitution modifier. Outside of combat, that basically means taking a creature’s Constitution modifier and multiplying it by 6 for a number of seconds they can survive while suffocating (since 1 combat round in D&D equals roughly 6 seconds or "real" time). Of course, some creatures have a +0 or negative Constitution modifier, so 5e’s suffocation rules give all creatures a minimum of 1 round (or 6 seconds) before they start dying.

So, a Barbarian with a 16 in Constitution has a +3 modifier. This means they can survive 3 rounds (or 18 seconds) once they start suffocating.

If you want a refresher on Ability Score modifier, see the table from this D&D Ability Scores article to see corresponding modifiers.

Next, after a creature suffocates, they drop to 0 hit points and start dying. Put differently; they drop to 0 hit points, fall unconscious, and start making death saving throws.

Typically, the best way to rescue a character making death saves is to stabilize them (via some method like a Wisdom (Medicine) check or spare the dying) or to heal them (through an ability or some kind of healing spell). But, the interesting thing about making death saves and 5e’s suffocation rules is a creature cannot be stabilized or gain hit points while suffocating. So, given enough time, a suffocating creature in 5e will die unless they become able to breathe again.

Here’s an example.

Let’s say the party including a Wizard (Constitution 10), Fighter (Constitution 16), and Cleric is taking a short rest along the edge of a forest. Suddenly, thick vines erupt from the earth and wrap around the Wizard’s neck and restrain the Fighter. The Cleric was far enough away to avoid being targeted. Now, these are tough, thick, possibly magically enhanced vines, so the Cleric and the Wizard can’t break the latter free. Since they were caught off guard, neither the Fighter nor the Wizard were able to catch their breath, so after 6 seconds, the Wizard passes out, falling unconscious and dropping to 0 hit points. Despite the Cleric casting healing word, the Wizard doesn’t regain lost hit points nor do they stabilize because the vines continue to squeeze their neck.

Of course, this is an extreme example, but you can see the danger suffocating poses for even high-level parties if they can’t start breathing after falling unconscious.

How Long Can a Character Hold Their Breath?

Player characters and creatures in D&D 5e can hold their breath a number of minutes equal to 1 + their Constitution modifier. As such, hardier creatures (that is, those with higher Constitution scores) are able to hold their breath for longer periods of time.

The rules for how long a creature can hold their breath can be found in Chapter 8 of the Player’s Handbook:

So, every creature in 5e can hold their breath for at least 30 seconds as the rules explicitly state the minimum. This is because a creature with a negative Constitution modifier would otherwise reduce how long their can hold their breath to 0 or even negative minutes which wouldn’t make sense.

After that, the base starts at 1 minute or 10 rounds of combat. You then add a player character’s or creature’s Constitution modifier to that.

As an example, a Barbarian with a 16 Constitution score has a +3 modifier. So, character would be able to hold their breath for up to 4 minutes before they start suffocating.

Now, this applies to Game Master-controlled creatures as well. So, a default Bandit can hold their breath for up to 2 minutes (12 Constitution, +1 modifier) and a Goblin can only do so for the base 1 minute (10 Constitution, +0 modifier).

Casting Spells While Suffocating in 5e

Reason stands that a spell requiring a verbal component can not be cast while suffocating in 5e. To cast these spells, the caster needs to have breath to incorporate the verbal component.

5e’s spellcasting rules specifically outline how Verbal components work in Chapter 10: Spellcasting of the Player’s Handbook:

Basically, spells requiring a Verbal component involve speaking. Verbal components don’t rely on the specific words, but more on the pitch and resonance. As such, a creature that is suffocating is usually unable to cast spells that need Verbal components.

A suffocating creature has no breath left. At that point, they wouldn’t be able to clearly dictate the Verbal components for their spells. Similarly, a creature getting choked or strangled wouldn’t be able to cast these spells due to their inability to properly breathe.

Now, if your character is holding their breath, your Game Master might allow them to expel their breath to cast a spell. But, after that, your character would start suffocating.

Of course, if a spell doesn’t require a Verbal component, a spellcaster may use it freely while suffocating (following any other potential restrictions like shackles or a lack of focus or Material components). Somatic components requires specific gestures and Material components work with either the specific items or a focus, and neither rely on a character’s ability to speak. So, spells like catapult or the new 2nd-level spell from Spelljammer: Adventures in Space air bubble could be cast while suffocating.

Simply put; if a spell requires a Verbal component, it can’t be cast while suffocating in 5e. On the other hand, if a spell doesn’t require a Verbal component, it may still be used even if the caster can’t breathe.

For GMs: Using the Threat of Suffocation in Your Games

Suffocation is a solid, mundane hazard to use in your games. While there are abilities to mitigate or negate the threat, most player characters, regardless of level, need to breathe and placing them in situations with rapidly depleting air challenges them differently than combat or even other non-magical obstacles.

The lack of breathable air is a much more difficult hazard to overcome than other obstacles like difficult terrain or areas that are heavily obscured. Many challenges player characters face have at least a few defined abilities for overcoming them. But, suffocation doesn’t have that many ways to get around it.

Very few spells and class features work in such a way to fill a space with breathable air. The magnificent mansion spell creates an extradimensional space to possibly escape suffocation, but it has a casting time of 1 minute, much longer than a character has before they suffocate; requires a Verbal component, so the caster can’t hold their breath; and is a 7th-level spell, meaning the character needs to be at least 13th-level to cast it to begin with. That said, Spelljammer: Adventures in Space introduced the 2nd-level spell air bubble which produces a small pocket of breathable air for 1 target creature. For low-level adventurers in a party of 3 or 4, that’s still a heavy price to pay since the caster may only be able to cast it on a couple of the player characters.

So, even high-level characters don’t have a lot of options for dealing with suffocation in 5e.

Of course, specific characters may have an ability to deal with a lack of air like the Air Genasi. But, that then gives that player a chance to shine while they figure out how to save the other characters.

Basically, you should use the threat of suffocation in your game more than the actual act. This usually means giving your players a time limit as their source of air depletes. Eventually, if the party can’t escape, they’ll start suffocating and things will become much more dire.

Some encounters you could introduce to use the threat of suffocation in your games include:

• A relatively large cavern experiences a cave-in, sealing off airflow giving the player characters a set amount of time before running out of air
• Water begins rapidly flowing into a sealed room, eventually filling it completely
• The building the party is in is enchanted to be airtight, putting a time limit on the player characters
• While investigating sunken desert ruins, a crack splits in the ceiling and starts pouring sand in at an alarming rate
• A sealed room has its perimeter erupt in flame, the fires start burning the oxygen faster than it can flow in and the smoke begins choking any creature within

Suffocation in 5e FAQ

Summary of D&D 5e’s Rules for Suffocating

That covers just about everything around how suffocation works in D&D 5e.

A creature can hold their breath for a number of minutes equal to 1 plus their Constitution modifier and for a minimum of 30 seconds. After that, a creature has a number of rounds equal to their Constitution modifier (or multiplied by 6 for the number of seconds) until they suffocate. At that point, they drop to 0 hit points and can’t become stable or regain hit points until their can breathe again.

Have you run an encounter with the threat of suffocation as a part of the danger? How would you work an encounter around the character’s holding their breath into your game? Leave a comment below with your thoughts!

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