Many male lizards and some other reptiles like snakes have hemipenes. These little reproductive organs are all fine and dandy until one decides to pop out and then stay out, creating a painful situation called a prolapse.
Understanding the Hemipenes
Hemipenes are moist, pink, fleshy, reproductive organs located just under and on either side of your male lizard's cloacal opening. Only males have them and they are not visible unless they are exposed. They are normally tucked away and appear as two small bulges underneath your lizard's cloaca at the base of the tail. This bulge, along with the presence of large femoral pores, are often the characteristics you would look for when determining if your lizard is a male.
Hemipenes are like miniature penises. They are little tubes used for mating but unlike humans, they are not used for urinating. They should not normally be exposed.
Why Would a Hemipene Be Exposed?
Sometimes hemipenes will come out if there are females in your male's line of sight or if your male feels another male is trying to be more dominant. One or both of his hemipenes may pop out and prolapse from these exposures to other lizards. Other times they will prolapse due to impaction, lack of humidity, or while purposely being sexed by a person ("popping" a hemipenes is one way to sex some reptiles, but most veterinarians don't recommend this). Sometimes hemipenenes will prolapse while removing excess skin and impacted/dried feces around the vent and won't go back in.
Diagnosis and Treatment
If you see a pink bulge or two under the cloaca of your male reptile it probably has a prolapsed hemipenis. You should call your veterinarian or an emergency exotic veterinarian for advice first. If they recommend this, sometimes lizards prolapse GI and not hemipenes which can appear similar at times, you can apply sterile lubricant onto the area then try applying firm but gentle pressure directly on the hemipenis with a moist cotton swab or your finger to retract it. If that doesn't work, try soaking the reptile in a warm bath with some sugar added for about 15 minutes or apply some medical-grade honey directly to the hemipenis. These sweet techniques can help decrease the inflammation and hopefully make the hemipenis retract. If these techniques don't work, bring your pet to an exotic animal veterinarian for help.
If a hemipenis comes out and stays out, it may also dry out. If you are unable to get the hemipenis to retract at home, keep it moist with warm water or apply some vaseline or another lubricant. Your exotics vet may have to sedate your reptile to retract the hemipenis, use a stitch to hold it in place, or even amputate it if it will not go back in and stay in. A hemipenis that stays out for too long can become infected and the tissue can die off. Therefore removing the prolapsed hemipenis is the best option to prevent a systemic infection from occurring.
Provide adequate humidity in your reptile's environment to assist in full-body sheds and to prevent hemipenes and femoral pores from becoming impacted. Don't purposely extract the hemipenes to sex them or clean them. If you suspect the hemipenis is impacted, soak your reptile in a warm water bath for 15 to 20 minutes before trying to clean it out- repeat as needed. If you are afraid the hemipenis won't go back in after gently attempting to replace it, do not continue to try- have your exotics vet handle it.
If other reptiles seem to encourage territorial behaviors and your males' hemipenes keep coming out, you should separate your reptiles and make sure they can't see each other from a different enclosure in the room.
Sometimes you can't prevent a prolapse but you can take all necessary precautions and be prepared if it does happen.