10 Top Reasons Why Guinea Pigs Lose Hair
There are many reasons why your guinea pigs lose hair. As a piggie owner, it’s important to know the causes so you can treat it. Here are 10 of the most common ones:
There are many reasons why guinea pigs lose their hair. One is a fungal infection, which appears as ringworm. Barbering (guinea pigs pulling out hair) also leads to hair loss.
Other causes include bumblefoot, ovarian cysts, and drooling. Parasite infections, hypothyroidism, and abscess also cause loss of hair. Female guinea pigs also lose hair when pregnant.

There’s many causes of hair loss in guinea pigs. If you can find and treat the cause, the hair loss will stop.
Keep reading to learn more about the different causes of hair loss and how to treat them.
1. Fungal Infections
Fungal infections mainly appear as ringworm. They cause excessive scratching in your guinea pig. This excessive scratching will cause self-induced trauma on the skin, leading to hair loss.
These ringworms mostly appear on the face. The main symptoms are:
- Itchy and dry skin
- Bald spots
Fungal infections don’t cause severe itchiness like mange mites. The primary cause of fungal infection in guinea pigs is Trichophyton mentagrophytes.
The treatment for fungal infections is with an antifungal cream. You can also clean the infected piggie with a recommended shampoo. Severe cases will need oral antifungal medication.

One of the most important ways to manage fungal infections is proper hygiene. Keep their cages clean and dry. And some piggie parents even bathe their piggies once every 3 months with a preventative anti-fungal shampoo. This’ll help your little buddy’s condition and also reduce the spread to other guinea pigs or even humans.
2. Barbering

Barbering guinea pigs is when they pull their hair or the hair of one of their cage mates.
The best way to tell barbering apart from internal causes of hair loss is that the hair didn’t come out from the roots.
Causes of barbering in cavies are:
- Stress
- Boredom
- Tooth pain
- Arthritis
- Asserting dominance
- Itching skin
- Allergic reaction
- Parasitic infection
If two pigs fight, they can get injured. This might cause an infection which can lead to hair loss. Sometimes one pig might pull out a chunk of the other pig’s hair during a fight.
Check out the post, Why Do Guinea Pigs Lose Hair Around Their Eyes? (Find Out Now) to learn more about guinea pigs hair loss.
When asserting dominance, they can cause serious injuries to each other. If one is weaker than the other, this can be very dangerous.
To control barbering, you should reduce the amount of stress in a guinea pig’s environment. Here are the steps you can take to treat and control barbering:
- Providing adequate space in the enclosure for hiding and maintaining hygiene.
- Separate the dominant piggie from the non-dominant if they’re fighting.
- Give them alternate chew toys so they stop barbering.
- Change your guinea pig’s diet by giving them crunchier things to eat to tempt them away from gnawing on hair
3. Overgrooming
Guinea pigs can sometimes over-groom themselves. This can be due to:
- Stress
- Pregnancy
- Fear
Overgrooming leads to loss of hair.
To reduce overgrooming, make sure your piggie is living in a stress-free environment. Ensure their enclosure has places to hide so that they can feel safe.

Check out these posts on common issues with guinea pigs – Hair: What You Need to Know About Why Guinea Pigs Eat It and Can Stress Kill Your Guinea Pig? (What You Need to Know)
4. Bumblefoot

Bumblefoot is a condition caused by guinea pigs stepping on wet surfaces. These can be wet carpets or urinated bedding patches. The constant wetness leads to a bacterial infection that causes swelling of the feet.
Guinea pigs have sensitive feet that aren’t covered in hair. When they sleep, they often put their weight on one side of their body which can lead to irritation and bumblefoot. This infection can cause hair loss.
Bumblefoot can affect a guinea pig at any age. When your pet has bumblefoot, visit the vet immediately.
The vet will probably prescribe antibiotics if the case is serious. The antibiotics are mainly meant to target the place that is affected.
Your vet can help your furry friend feel better by prescribing medicine to help with the pain. They can also provide advice on cleaning and caring for the wound, medicated baths, and wrapping.
Bumblefoot can take time to heal. It doesn’t heal overnight. Your pet will need care multiple times a day.
In some very serious cases, veterinarians might have to amputate your pet’s foot to save their life. But, don’t freak out. If you catch it early enough, this usually isn’t necessary

The best way to prevent bumblefoot in guinea pigs is to make that you keep their enclosure dry. Spot clean their bedding every day and make sure to deep clean it completely every week.
5. Ovarian Cysts
Ovarian cysts can lead to abdominal swelling that can cause hair loss on both sides of the stomach. Ovarian cysts don’t cause itching. Ovarian cysts are pretty common in female guinea pigs.
This can affects sows up to 5 years old. Puberty in female pigs is triggered by androgens, which are produced by the female body. This leads to the stimulation of hair growth.
Female pattern hair loss is a disorder of excess androgens that leads to thinning hair. Guinea pigs with this disorder will grow thicker hair on their faces, but they will also lose hair and become thinner.
Even though the lost hair can’t be recovered, new hair can grow through treatment. Hormonal imbalance also causes hair loss in female guinea pigs.
Sometimes a vet will prescribe supplements to help prevent the hair loss. But, make sure you don’t self-medicate your piggies. Always consult a piggie-savvy vet first.
Removal of ovarian cysts is another way to completely cure the condition. But, the surgery isn’t without risks. And it can be especially dangerous if your piggies is older or already in poor health.

If you want to learn how having ovarian cysts can affect a female guinea pig’s life, check out: 10 Common Causes of Guinea Pig Death (Piggie Parents Weigh In) and Can You Separate Bonded Guinea Pigs? (Find Out Now)
6. Drooling
Drooling can cause hair loss. If a guinea pig overeats, they will drool. It is important to control how much your piggy eats so they don’t drool as much.
Slobbering is caused by overgrown teeth. Both slobbering and drooling can lead to saliva constantly dripping below the jaw and wetting the hair under their jaw.
The constant wetness can cause itchiness, bacterial infection, and ultimately, hair loss. Drooling can also be normal for guinea pigs, but you should always check for unusual signs. If you are unsure, you can check with a vet.
The treatment for drooling is mainly watching their diet. Make sure it’s healthy and not excessive.
For slobbering, which shows itself the same way as drooling, check their teeth. It could be the front or back teeth. When their teeth overgrow, they trap the tongue, leading to slobbering.
The most basic treatment for overgrown teeth is to give your guinea pig a mix of dry food and water. This way they can chew on it and wear down their teeth.
Your guinea pig’s diet should be 80% hay that can wear their teeth down.
If there’s an infection, a vet will suggest an antibiotic for treatment.

Don’t have the vet trim your piggie’s teeth with scissors unless absolutely necessary. It’s better to wear down their teeth naturally with LOTS and LOTs of hay.
7. Parasite Infections

Parasitic infections in guinea pigs are caused poor hygiene. This leads to bald spots. Mange mites are the main cause of parasitic infections in guinea pigs.
The main symptom is mites is your piggie itching their skin. The itchy skin leads to wounds that look like the piggies were fighting.
Having an itchy pig can cause stress. This might lead to the piggie fighting with others, which will spread the infection.
Mange mites are very small and can only be seen using a microscope. They live in and eat the skin of your little furry potato. In extreme untreated cases, they can lead to seizures and even death. The mites also lead to dandruff which also causes hair loss.
For treatment, seek a vet’s help. The best way to treat parasitic infection is to spray cavies with ivermectin. You will need to spray your little buddy several times. In severe cases, you might have to spray your little buddy three times.
Remember to consult a vet if you are going through this. Guinea pigs also need to be bathed regularly.

Bathing a piggies that has mites will cause the mites to burrow deeper into their skin which causes an intense amount of pain. Always get a diagnosis from a vet BEFORE you treat your fur babies for a hair loss infection.
8. Hyperthyroidism
Hyperthyroidism is a condition where the thyroid gland produces too much thyroid hormone.
This used to be thought to be rare in guinea pigs, but recent studies suggest that it might be more common than at first though.
This condition causes serious problems in parts of the body such as the lungs, heart, and kidney.
The main symptoms of hyperthyroidism in guinea pigs are:
- Enlarged thyroid nodules – a palpable mass can be felt in the ventral cervical region.
- Frequent and excessive urination – might not be as easy to observe.
- Excessive energy – piggie becomes super active.
- Increased thirst for water
- Weight loss – their weight will drop even though they eat more than usual. The weight loss is steady and can be observed.
- Increased temperature and restlessness – your little furry will seek out cooler surfaces and avoid warm bedding. He will also be warmer to the touch than other guinea pigs.
Prolonged and severe hypothyroidism can lead to hair loss. The entire scalp will become hairless, not just in certain spots. The hair will look uniformly sparse.
After thyroid disorder treatment, there is often some regrowth. However, it may take several months for the regrowth to be complete. Even then, it might not recover entirely.

If your guinea pig is showing symptoms of hypothyroidism, take them to a piggie savvy vet to get an accurate diagnosis.
9. Pregnancy Associated Alopecia

Alopecia due to pregnancy happens to female guinea pigs. The sow’s hair thins or they experience hair loss when they get close to the time when they have to start nursing their babies.
This comes about when hormones for pregnancy affect hair growth.
It tends to happen in the last stages of pregnancy.
This condition is normal for pregnant sows so don’t be too scared when it happens. You should only be concerned if it persists during the pregnancy. When this happens, please consult a vet.

Guinea pig owners know that these little creatures are sensitive. They get stressed easily by loud noises or sudden movements. This can have a bad effect on their health. This is especially true for pregnant guinea pigs, who need a calm and stress-free environment to make sure their pregnancy is healthy.
10. Abscesses
An abscess is an infection that can form on the skin or in the mouth. Abscesses in the mouth of guinea pigs are often caused by overgrown teeth.
Because guinea pigs’ teeth never stop growing, they need to chew hay to wear them down.
An abscess is a painful, pus-filled that forms on the surface of the skin. It becomes warm and swollen, and often has a capsule around it. The hair on the affected area may also fall out.
I wrote about more about abscesses in Will an Abscess Kill a Guinea Pig? (What You Need to Know). You should check it out.
Abscess treatment needs veterinarian assistance. A vet will drain the capsule and dress it properly. In case of abscess bursts, make sure to cover the surface using a microscope tape to prevent infections.
Clean the wound with disinfectants to prevent infections. Also, feed your fuzz spud lots of vitamin C. Vitamin C helps in boosting their immunity.

An abscess can be a symptom of other problems. Please consult a vet when your guinea pigs develop one. Remember to examine your little pet every day for any signs of infection.
Common Reasons Why Guinea Pigs Lose Their Hair (Pet Parents Weigh In)

The main causes were stress, pregnancy, ringworm, and mites. Other causes are ovarian cysts and shedding due to the warm season.
Many guinea pigs lose their hair. I wanted to find out more, so I surveyed some parents.
I manually surveyed 65 guinea pig parents to know the reasons their pets lost their hair:
- 22 of the respondents (34%) were caused by stress. Piggie parents noticed their pets pulled their own hair too much. Some parents increased the time they spent with their pets. Others separated the bonded pair after they noticed bullying.
- 14 of the responded (21%) were due to mites. Pet owners had noticed itching and scratching which worsened over time. After examination, they determined it was mites. They got their guinea pigs sprayed and gave them a bath regularly.
- 12 of the respondents (18%) were because of ringworms. In several of these cases, piggie parents noticed hair loss around the eyes. After a vet visit, they confirmed it was ringworm and got their pets treated.
- 6 of the respondents (9%) were due to pregnancy. Their sow’s hair thinned when the sow was pregnant. The condition got better after the pregnancy.
- 6 of the respondents (9%) were caused by ovarian cysts. For some parents, the condition persisted even after surgery.
- 2% of respondents said the hair loss was caused by shedding due to the warm season.
Many parents were concerned about hair loss in their guinea pigs. They turned to vets and other pig owners for help to understand what was happening. Hair loss is a common issue for guinea pigs.
- Consulting a vet was pretty standard for many parents. Especially when the hair loss showed scabs or wounds.
- Treatment for hair loss worked for many pet owners. Their piggie was able to regrow their hair soon after.
- Mites were pretty common for many piggies. The excessive itching was the main sign of mites.

Hair loss can be a symptom of an underlying condition. If you notice that your pet is losing hair, the best step to take is to go to the vet. This will help you rule out any health concerns. Make sure you have a pet fund saved up in case of emergencies like this.
How Can I Stop My Guinea Pig From Losing Hair?
Consult a vet to determine the cause of the hair loss. The vet will also prescribe medication for your piggie.
In case of fungal infection, you should use an antifungal cream. For bacterial infections, spray your pet with ivermectin. A regular bath is also necessary to control the condition causing hair loss.
Another step you can take is to give your guinea pigs zinc supplements. They boost hair growth. Give them chew toys to reduce barbering. Apply lemon to their fur to discourage barbering from others.
Providing your pets with adequate, clean space will also reduce stress. Stress can cause hair loss. Make sure their bedding is highly absorbent.
Vitamin C is also quite good for boosting their immune system. This will help treat the hair loss causing condition.
Give your piggies a proper diet and constant hay to help with their digestion. This will not only wear down their teeth but also prevent drooling.

Make sure your little fur babies live in an enclosure lined with soft and clean bedding. The enclosure should have proper ventilation as well. A clean and dry enclosure will keep away bacteria and parasites.
Why Does My Guinea Pig Have Bald Spots?

Bald spots in guinea pigs can be caused by barbering, ringworms, injuries, and alopecia.
Barbering is when a guinea pig pulls its own hair or others’ hair.
Ringworm can also cause bald spots on the affected area. Injuries can cause infections that will lead to hair falling off the affected spot.
Alopecia can be caused by a number of factors including genetics or pregnancy.
Are Guinea Pigs Supposed To Lose Hair?

Yes, it’s normal in small amounts. Guinea pigs like any other fur animals shed hair while grooming or when it’s too hot.
It only becomes concerning if they develop bald spots or lose huge chunks of hair. Their hair thinning is also a concern.

You’ll find this post helpful: Why Do Female Guinea Pigs Spray Urine? (The Honest Truth)
Does Guinea Pig Fur Grow Back?
Yes, more often than not, guinea pigs’ fur grows back. Guinea pig hair grows back in a few weeks to months.
After treatment of the cause of the hair loss, you should see improvements in your cavy’s hair loss.
Unless the condition is permanent and damages the hair root or is alopecia. In some cases, the fur might not grow as well as before.
Things to Remember About Guinea Pig Hair Loss
- Hair loss is not an isolated case with guinea pigs. So if your pet is having this problem, don’t worry and consult with a vet.
- Most causes of hair loss are treatable.
- Good hygiene is key in keeping your piggy’s fur healthy. A regular bath with shampoo will help prevent many skin conditions that cause hair loss.
- Regularly inspect your guinea pig. Examine their head, ears, eyes, under their belly, and all over their body. This way, you will stay on top of any condition that might come show.
- Hair loss can be a sign of other serious problems with your piggie. Remember to watch out for it.