Why is my crested gecko not eating?

Temperature first — this species is heat-sensitive

Unlike most reptile diagnostics where "is the warm side too cold?" is the first question, with crested geckos (Correlophus ciliatus) the first question is "is the room too warm?". Per ReptiFiles' care guide and Zen Habitats' Q&A:

• Comfort range: ambient 22–26 °C (72–78 °F).
• Genuinely dangerous: sustained above 28 °C (82 °F).
• Often fatal: sustained above 30 °C (86 °F).

Crested geckos evolved in cool New Caledonian forests. They cannot thermoregulate at high temperatures the way desert reptiles can — heat stress is the documented #1 captive mortality cause.

Quick check before any other diagnostic:

• Room temperature with a digital thermometer.
• If approaching 28 °C, cool the room (open windows, AC, frozen water bottles wrapped in towels placed near but not in the enclosure).
• Sustained refusals in summer almost always trace to heat stress before they trace to anything else.

The five common causes

In rough order of frequency:

Cause 1 — Heat stress

See above. Most common cause in summer or in warm homes.

Cause 2 — Rehoming stress

A newly-acquired crested gecko almost always reduces or refuses feeding for 1–2 weeks. Standard protocol:

1. First 2 weeks: zero handling. Brief visual checks only.
2. Offer CGD nightly in a shallow dish on the feeding ledge, remove untouched portion in the morning.
3. Calm room conditions — no loud noise, no pets visible through the glass, low traffic.
4. Dim red night light is fine for observation if you want it; never white light at night.

Most new geckos accept food by the end of the second week. If refusal extends past 2 weeks with a new arrival, audit temperature and humidity, and consider a vet check.

Cause 3 — CGD flavour rejection

Crested geckos can be flavour-picky. Per PetMD's care sheet, commercial CGD comes in multiple flavours and brands:

• Repashy Crested Gecko MRP (multiple flavours).
• Pangea Fruit Mix Complete (multiple flavours, with and without insects).
• Black Panther Zoological Complete Gecko Diet.
• Lugarti Premium Crested Gecko Diet.

If your gecko has been on one flavour and stalls, rotate to a different flavour at the next feeding. Many keepers maintain a 2–3 flavour rotation to prevent this. Don't switch entirely to a new brand overnight — gradual rotation keeps the gecko adapted.

Cause 4 — Shed cycle

Crested geckos shed every few weeks (juveniles) to every 1–2 months (adults), and often refuse food for a day or two around the shed event. They typically eat the shed skin. Single-day refusals around obvious shed cycles are routine. See the humidity guide for shed cycle management.

Cause 5 — Underlying illness or husbandry issue

Less common but worth ruling out:

• Metabolic bone disease (rare with proper CGD) — soft jaw, weak grip, kinked spine.
• Floppy tail syndrome — tail rests bent forward over the body. Often calcium-related; can also indicate poor vertical climbing space.
• Parasites — uncommon in captive-bred but possible in wild- origin geckos.
• Stuck shed — toes or tail tip with retained shed, sometimes interfering with movement and feeding.
• Recent tail drop — see the dropped tail guide; gecko often refuses food for several days post- drop.

Triage by duration and signs

What to do — and what not to do

Do:

• Check temperature first with a digital thermometer.
• Try a different CGD flavour at the next feeding.
• Offer live insects (2–3 appropriately sized crickets, dubias, or BSFL) in the evening as a feeding-trigger experiment.
• Reduce all stressors — handling, visible pets, loud noise.
• Weigh weekly during any refusal period. A simple digital kitchen scale and a deli cup work.
• Track everything — see the husbandry log guide.

Don't:

• Heat the enclosure in response to refusal. The opposite is more often needed in this species.
• Force-feed — stresses an already-stressed animal.
• Switch entirely to insects. CGD provides complete fortified nutrition; an all-insect crested gecko diet eventually causes calcium deficiency.
• Handle a refusing gecko "to check it" beyond a brief visual.

When to see a vet

The thresholds above. Bring a written husbandry log and weight trend to any reptile-vet visit — significantly speeds diagnosis. The pillar care context is in the pillar care guide; the cross-species early warning patterns are in "is my reptile sick?"; the humidity setup that's often involved is in the humidity guide.