Reptile Molting

Reptiles shed their skin, or integument, four to 12 times per year. Shedding allows for roomier growth and removes harmful parasites.


During this time snakes rub their heads against surfaces to help loosen the old skin. You may also notice your iguana puffing up their eyes 2-3 times their normal size.


For reptiles, shedding is a natural process that occurs periodically. Shedding is the formation of a new layer of skin, discarding old layers that are no longer useful. The new skin is usually a little lighter than the original, and it may contain some blood vessels. A secretion is usually released between the new skin and the old skin to lubricate the detachment process.

Reptiles such as snakes, lizards and turtles shed their skin on a regular basis. This is called ecdysis or moulting. Birds, mammals and amphibians shed their feathers, hair and fur on a regular basis as well.

When a snake is ready to molt it will start rubbing its head on rocks or other abrasive surfaces. The skin will then start to split open. Once the skin is completely shed it is turned inside out and the snake slithers out of it, much like taking off a sock.

Snakes will also change color before a shed. Boas and pythons will become darker, while colubrids will lighten up. During a shed, the skin should be gently pinched between the thumb and index finger and then pulled upright (tented). The time it takes for the skin to return to its original position is indicative of the degree of dehydration. It is important to feed the snake properly during this period.


The incubation phase of reptile molting is the period before a new skin starts growing. This process can last a couple of weeks depending on the size and condition of the snake. During this time, it is critical to allow the snake or lizard to shed and moult without disturbance. If the shed skin is not allowed to fall off, it can trap bacteria or parasites beneath and restrict blood flow. This can lead to infection, blindness or even death.

During this period, the basal cells of the skin start to move upwards. These cells eventually form a new layer of skin which pushes the old layer off. The new layer will then grow over the entire body and replace all the outer layers of the animal. This process is known as ecdysis.

In some animals, such as birds or mammals, the old layer of skin is eaten. In others, like reptiles, this is not the case. The old layer is replaced with a fresh new layer of skin which will also grow bigger scales that can no longer fit in the previous skin.

Reptiles such as snakes, lizards and turtles molt on a regular basis to keep their integument fresh and prevent infection. The molting of these organisms is regulated by hormones. The old layer that is replaced is called exuviae and the occurrence of shedding is known as ecdysis.


Many animals shed feathers, hair, or skin on a regular basis to make room for new growth. It’s called molting, or sloughing in some cases. Birds molt on a seasonal basis to grow lighter summer feathers. Mammals like deer shed their heavy winter coats to make room for their lighter spring coat. Snakes and lizards also shed their outer skins.

Unlike mammals, reptiles don’t slough their skins off little by little. They typically slither out of their old skin in one piece, similar to taking off a sock. This process is known as ecdysis, and it’s what makes a snake look so cool when it’s shedding!

The underlying cuticle is made of two layers, the epicuticle and the exocuticle, with a layer of chitin between them. The epicuticle is deposited before the sclerotization of the exoskeleton and cannot expand afterward, while the exocuticle and endocuticle can expand. The sclerotization of the exoskeleton prevents the cuticle from expanding further, and thus the insect must molt to gain more space inside its body.

The molecular signaling pathways involved in ecdysis are quite complex and vary between different animal groups. De Oliveira et al’s study is an excellent contribution to understanding this complexity, and their phylogenetic analysis of the components involved is well done. The authors also call for further functional studies of these pathways to better understand the evolutionary plasticity that occurs.

Post-molt Care

In the post-molt phase, your reptile will be much more active than usual. They will want to eat but it is important that you do not feed them yet because the fangs have not hardened up. During this time you can give them vitamins in their water or ground up egg shells mixed in their food to help their new exoskeletons become hard. Make sure that they have plenty of water available at all times, as they will be more thirsty than hungry during this period.

Shedding can take days to a couple weeks depending on the size of your snake and body condition. During this period, the snake will rub its head on something abrasive to rip open the outer layer of skin. Once a rip is created, the snake will begin to peel off the old skin from its mouth and nose area like a child peels off a sock. This process is called ecdysis.

Reptiles shed their skin on a regular basis to allow the newly formed layer underneath to grow and mature. Shedding is a very important part of your reptile’s growth and can be a good indicator of health. If your reptile is not shedding on a regular basis, you should check its diet and environment for issues that may cause this.