Mouth Rot (Infectious Stomatitis) in Green Iguanas

Mouth rot, or infectious stomatitis, is a bacterial infection along the gum line that in green iguanas often starts at a point of minor trauma — repeated nose-rubbing against enclosure glass during a period of stress or territorial agitation, or an impact from striking hard decor, both create small entry points where the mouth's normally balanced bacterial population can become invasive.

This species carries a specific additional risk factor worth flagging: a jaw already weakened by metabolic bone disease is measurably more vulnerable to mouth rot, since softened bone and gum tissue heal more slowly and resist infection less effectively than healthy tissue — a keeper managing an iguana through MBD treatment should watch the gum line more closely than they otherwise might, since these two conditions compound each other in practice.

A territorial or stressed iguana repeatedly nose-rubbing the same stretch of glass day after day is quietly wearing down the same small patch of gum tissue with each pass — no single rub looks like an injury, but weeks of the identical repeated contact adds up to real cumulative damage, and this pattern tracks closely with the seasonal restlessness mature males go through each year.

An iguana with this condition often shows it first at feeding time rather than at rest — hesitating over a leaf it would normally grab readily, chewing on one side, or dropping food after taking it — before a keeper spots the gum swelling or discharge directly. Any hesitation like this paired with a look inside the mouth showing puffiness or an off-color patch along the gum needs a vet visit rather than a wait-and-see week, since this condition tracks into deeper jaw and bone tissue if left untreated — a genuinely serious outcome in an animal whose jaw may already be structurally compromised by MBD.

An iguana whose infection is caught at the redness-only stage generally responds well to a cleaning-plus-antibiotics course and heals without any lasting mark on the gum. Wait until the jaw bone itself is involved, though, and full recovery gets a lot less certain — which is the practical case for treating first redness as worth a same-week vet call rather than a few more days of watching.

An iguana biting down hard on a tough stem can show a bit of transient gum redness that's gone by the next day with no swelling attached — that's ordinary and not worth a vet call on its own. What separates it from real stomatitis is simply whether it clears on its own or instead sticks around and starts looking worse.

A vet treating confirmed stomatitis will typically also want to review overall calcium and UVB status even if MBD hasn't been formally diagnosed yet, given how closely the two conditions interact in this species — correcting only the visible infection while leaving an underlying bone-health gap unaddressed sets up a real risk of the same problem recurring once the antibiotic course ends.

Feeding behavior is worth reviewing too: an iguana offered oversized, poorly chopped food pieces that require excessive tearing and biting force to manage is at somewhat higher risk of the kind of repeated minor gum trauma that contributes to this condition, distinct from the boundary-testing and MBD pathways covered above — appropriately sized food reduces this risk alongside its role in preventing impaction.

Chronic low-grade stomatitis that keeps recurring after apparently successful antibiotic treatment is worth investigating for an ongoing environmental trigger rather than treating each flare-up as an isolated, unrelated event — a persistent source of nose-rubbing trauma, an enclosure surface that's never been fully disinfected between episodes, or an unresolved calcium deficiency can all keep reintroducing the same infection pathway even when each individual course of antibiotics does clear the visible infection at the time.

If the first antibiotic isn't turning things around within the expected window, a swab sent for culture identifies exactly what's growing there — worth doing rather than simply extending the same prescription and hoping, since the second, culture-matched round tends to clear a stubborn case far faster than guessing again.

Comfort during the treatment period matters for recovery too — an iguana with a sore mouth from stomatitis may temporarily prefer softer, more finely chopped food over its usual chunkier salad mix, and accommodating that preference for the duration of treatment supports adequate nutrition intake without forcing the animal to work harder than it comfortably can while the gum line heals.

Fading redness at the end of the antibiotic course looks like good news, but it isn't proof the infection is actually gone at the tissue level — booking the follow-up exam anyway, rather than calling it done from appearance alone, is what actually catches a case that's smoldering under the surface in an iguana whose underlying MBD or trauma trigger is still unresolved.

A secure, well-designed enclosure with minimal reason for repeated boundary-testing against glass reduces the trauma pathway specific to territorial or stressed iguanas.

Managing metabolic bone disease proactively (correct UVB, calcium, basking temperature) protects jaw integrity and reduces this species' particular vulnerability to secondary mouth rot.

Consistent, correct temperature and low chronic stress support the immune resilience that keeps the mouth's normal bacterial population from becoming invasive.

A quick visual gum-line check during routine handling catches early redness or swelling well before visible discharge develops.