Axolotl deworming

How to Treat Intestinal Worm (Nematodes) Parasites in Axolotls

How to Treat Intestinal Worm (Nematodes) Parasites in Axolotls

"Can axolotls get worms?"


They are deadly if left untreated, but let's learn more about how to tell if your axolotl has worms.

What Kind of Worms do Axolotls Get?

Capillaria is a type of roundworm, or rather is a group of several other types.

The most common among axolotls is capillaria philippinensis.

The exact species of capillaria isn't important to know, but rather, to figure out if that is what your axolotl has.

8 Symptoms of a Wormy Lotl

Your axolotl may show one or more of the following symptoms if infected:

1. Visible white worms at the bottom of tank

This is usually the first sign of a worm problem.

This is usually because the axolotl has passed the worms either through regurgitation or through a bowel movement.

Please do not confuse this with detritus worms!

Not all white worms in your tank are bad!

Some are very important.

Wriggly little creatures like detritus worms, planaria, leaches and some other worms are a natural part of the ecosystem in the aquarium and, in moderate numbers, do not pose a threat to the axolotl.

They exist primarily to break down waste and feed on tiny microorganisms.


Infectious nematodes like capillaria are different - they eat on the axolotl directly from the inside, causing inflammation of the gut and many other problems.

They generally appear larger and thicker than regular tank flora worms.

2. Cachexia (Weight loss)

Alone, weight loss can indicate simply an improper feeding regimen.

But if the axolotl is well fed with proper foods at proper intervals, yet remains skinny... it is a sign the axolotl is wasting.

3. Inappetence

Lotls with a moderate load of worms will generally still eat normally.

But when things get bad, axolotls that are resistant to all attempts of feeding despite looking skinny are really feeling under the weather and have a high parasite load.

4. Bloat/abdominal swelling

I just mentioned how weight loss is a symptom of worms, probably one of the classic ones most people think of.

It might seem counterintuitive, but bloating is also a symptom.

Often the axolotl balloons up so large it is unable to regulate its buoyancy and floats upside-down at the surface, stomach distended.

Sometimes swelling can also be seen around the cloacal region.

5. Vomiting

Axolotls vomiting is often overlooked as a symptom of worms, but if your axolotl is vomiting, one of the first things to investigate is a potential worm issue.

The vomit will often be partially or entirely comprised of worms (ew).

If the axolotl is vomiting white worms, you will know right away it has a nematode problem.

6. Gill degeneration

The gills say a lot about an axie's overall health, and while some wormy lotls still have normal looking gill filaments in early stages, in later stages it almost always causes the axolotl to lose their floof.

The axolotl is struggling to get proper nutrition due to the worms sucking nutrients from the animal which are essential to beautiful gills.

7. Sudden (unexplained) death

The water parameters may seem fine, but then out of the blue the axolotl is found dead - this can be a sign of internal parasitism.

Usually there is some sign the axolotl has a worm problem to begin with, but many times it goes undetected until the axolotl just expires due to a high parasite load.

Very sad :(

8. Surface Surfing

This is a sign the worm infestation is very progressed.

The axolotl will swim for a prolonged period of time along the surface of the water with its head halfway out, as though it is trying to take a gulp of air, but can't.

Method of Diagnosis

Besides visually identifying worms that have come out of the axolotl, a veterinary diagnosis of worms in axolotls usually consists of microscopic examination of the feces for the barrel shaped capillaria eggs with "capped" ends.

As a hobbyist operating independently of veterinary assistance, you can use the symptoms above as strong indicators of whether it is likely your axolotl has worms.

Or, if you are especially nerdy or just want that final level of confirmation, you can use a high powered microscope to check the squashed feces yourself on a glass slide, if you know what to look for.

If you can, this is a good thing to do whenever you acquire a new axolotl.

Mode of Transmission

I want to bust this myth right out of the gate...

Axolotls do NOT get worms from the following sources:

  • Feeding live earthworms
  • Feeding live blackworms

How do they get them then?

They get them the same way people get them: from eating contaminated live fish.

(Or from coming into contact with contaminated water that contains nematode eggs from contaminated live fish; i.e. shared equipment, shared decor, water splashes, etc.)

While most of us don't go around eating livebearers out of the tank at Petsmart, people can get capillaria infections from ingesting raw or undercooked seafood that is contaminated with parasites (more on that later).

But in the case of axolotls...

Fish ingests worm -> worm remains in fish -> axolotl ingests fish with worms -> worms remain inside axolotl until axolotl gets really sick.

See, worms can remain in the axolotl for a long time before they multiply to a number large enough to cause an issue.

Sometimes it can be months after the axolotl eats the contaminated fish that it starts deteriorating.

This is why it is so, SO important to quarantine properly!

At the risk of sounding overbearing...

NEVER, EVER throw fish immediately in your axolotl tank you just got from the big box pet store!

Capillaria is just one of the diseases those fish can bring into your tank.

Breed guppies or other feeders from a clean source yourself or get them from a trusted breeder if you want to offer live fish as a food source.

If your axolotl has worms and you have never fed live fish, it is safe to assume the source where you got your axolotl had contaminated fish as a food source.

Now, the other way is from another axolotl.

Worms can spread rapidly from lotl to lotl when a system is contaminated with just one sick animal.

Quarantining new axolotls separately from the others is a very good idea to catch and treat anything before it spreads.

Capillaria is Transmissible to People!

Capillaria worms in axolotls can spread to people.

It is a zoonotic disease.

If you deal with axolotls (especially rescues), you need to know how to protect yourself.

While infections are generally rare, it is important to practice the following habits, especially if you suspect a nematode problem:

  • Wash hands after tank maintenance/interaction
  • Wear aquarium safe gloves if possible while working around the axolotl
  • Never use your mouth to start your aquarium siphon
  • Do not leave open drinks in the same room as the aquarium
  • Maintain a sanitary environment by washing surfaces with soap and water
  • Do not share equipment between tanks or disinfect between sharing tanks

If you suspect you have a capillaria infection, contact a medical professional. Left untreated, capillariasis is fatal and requires a quick and accurate diagnosis.

Medication & Treatment Options

Praziquantel (sold under the trade name of Prazipro) is NOT the drug of choice for this issue.

While it is effective against tapeworms and flukes, infestations of capillaria are not touched by this medication.

So, what are the options?

  • You can dose the water with Levamisole (sold under the brand name of Fritz Expel-P here in the US)
  • You can feed Fenbendazole gel food (long term; does not kill eggs)
  • You can inject the axolotl with Levamisole (vet recommended only)
  • You can feed natural deworming food (may be most effective as a preventative)

Water changes are your friend during this time.

While not essential, vacuuming the bottom frequently is recommended to remove dead worms and their eggs, helping to speed up recovery.


Cross-contamination can happen easily between infected tanks by sharing nets, siphons, or moving anything between tanks.

Do not share any equipment between tanks when you suspect one is contaminated.

It is most likely that allowing 2 hours of total drying will kill any eggs of worms, but that time could vary depend on the exact variety of worm you are dealing with.

For axolotls that are showing symptoms of worm infestation or as prevention, levamisole is a reliable option.

Keep this in mind:

Levamisole is a very gentle, safe treatment for axolotls.

Any heavy losses are not a result of the levamisole.

They are a result of the worms killing the animals.

In a bad infestation of nematodes, you can expect 50% loss of stock regardless of treatment, and that's if you are doing well. 75-100% losses can result from an outbreak depending on conditions.


If you lose your axolotl to this disease and want to start completely over, you can restart the tank by "bombing" it with vinegar, bleach, etc.

Boiling and freezing is also effective at killing the eggs and worms.

Of course, this will kill all plants and beneficial creatures as well as nuke the filter (where worm eggs could be residing anyway) so you will have to start over on cycling.

Advanced capillaria infections in axolotls are extremely difficult to reverse.

It is also recommended to bomb the tank and start over if you have been experiencing heavy losses, euthanizing all remaining animals first.

Natural Deworming Food Recipe

This "home remedy" is a good preventative measure you can take for new axolotls that you don't want coming down with worms. It can also be useful in the case of an animal with mild to moderate symptoms of a worm infection.

I would recommend coupling it with regular tank vacuuming/tubbing as it is not clear whether this food merely acts as a laxative, temporarily paralyzing the worms until they are excreted from the system, or if it actually kills the worms.

It consists of a 2 part treatment protocol I have found effective in my own animals, fish and axolotls included.

They usually need to develop a taste for this food before they will eat it at full strength.

Round one:

Bring water to a boil. Mix powders together and whisk into water. Pour into a container of choice and immediately refrigerate. Feed this mix for 3 days.

Round two:

Prepare food as instructed above. Feed this mix for 3 days. Repeat round two in 2 weeks.


How to help prevent nematodes in axolotls?

  • Quarantine all new axolotls for a minimum of 2 weeks (preferably 4 weeks or longer)
  • Feed a natural deworming food or treat with levamisole to help flush out any intestinal parasites during this time
  • Do not share equipment between axolotls in quarantine and those in the main tank
  • Avoid feeding live feeders from pet stores
  • Vacuum the substrate regularly


Worms in axies are generally treatable if caught in time, and easier to prevent than to treat by far.

I hope this post helped you!

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