Retractable leashes and their risks: why I no longer use one

Reading time: about 8 min

I have used retractable leashes myself. They once seemed convenient: the dog could wander a little farther, the line wound itself back in, and I did not have to gather a long lead off the ground. Today I do not choose them for my dogs. Not because every walk with one is dangerous, but because I have seen how quickly convenience can turn into loss of control.

I also have first-hand experience: with my former dog, who weighed around 38 kg, the locking mechanism on a retractable leash designed for large dogs broke twice. The leash was within the manufacturer’s stated weight limit. This does not prove every lock will fail, but it raised a very practical question for me: do I really want to entrust the safety of my dog and other people to a small brake button?

More freedom on a longer leash, but more control?

A retractable leash allows the dog to move farther away while a spring mechanism keeps its cord or tape under tension. On a quiet, empty path, this can seem to work perfectly well. The problem starts when a dog suddenly notices another dog, a bicycle or an interesting scent and moves several metres faster than the person can react.

When the dog is already far away, bringing it closer requires several actions: pressing the lock, shortening the line and assessing the situation at the same time. With a regular fixed-length leash, I know the distance from the start. VCA’s behavioural advice favours an ordinary leash in urban surroundings and a separate long, non-retracting line when more freedom for sniffing is appropriate.

I have experienced this while running. A woman approached with her dog on a retractable leash. I was running along the right-hand side of the path when the dog suddenly moved directly into my route: the dog was on the right, the owner on the left. She could not react quickly enough and I had to pass both of them on the left. This is one reason I dislike retractable leashes. In an unexpected situation, the owner may simply be unable to bring the dog under control in time.

Why does sudden stopping matter?

When a dog reaches the end of the line or the owner abruptly presses the brake, a powerful jerk can transfer force to the dog’s body. With a collar, the load goes to the neck; with a harness, it goes to the torso. Its effects depend on the dog’s speed and weight, leash length, attachment point, harness fit and the abruptness of the stop.

A 2020 study measured the pressure created by different collars on a simulated canine neck under pulling and jerking conditions. The pressure varied according to collar and force; none of the collars tested eliminated potential injury risk. This was not a clinical study of living dogs, so it cannot tell us how often a particular disease develops during real walks.

Dr Peter Dobias has written about retractable leashes repeatedly, and in much greater depth than the simple warning that a leash might break. His central concern is repeated loading of the neck and nervous system, with effects that, in his clinical experience, are not always linked back to the leash. This perspective deserves proper attention. We need to distinguish what he has observed, what anatomy and measurements can support, and what remains a clinical hypothesis rather than proven causation.

What exactly worries Dr Peter Dobias about retractable leashes?

Dobias distinguishes two forces. The first comes from the reel’s spring, which maintains some tension as the cord or tape extends. If the leash attaches to a collar, that tension is partly transmitted to the neck. The second and, in his view, more serious problem is abrupt stopping: the dog has built up speed, but movement suddenly ends at the limit of the line or when the brake is pressed. The load then differs greatly from that of a peaceful walk. The spring force depends on the particular device; there is no evidence that all retractable leashes cause identical neck damage. That does not make sudden jerking impossible.

The neck is not merely a convenient place to attach a lead. It contains the larynx and trachea, carotid arteries, jugular veins, thyroid gland, important autonomic nervous pathways and the cervical spine. These structures are not equally exposed: some are protected by muscle, cartilage and their anatomical position. Nevertheless, a collar can exert pressure on the neck during pulling. Dobias’s practical question is simple: why place avoidable load on that region when force can be distributed elsewhere?

His warning is not limited to retractable leashes. He also advises against attaching an ordinary lead to a collar, especially for dogs that pull hard or lunge. For retractable leashes, he adds the spring’s continuing pull and uneven braking to his list of concerns.

Paw licking and front-leg lameness: could the problem begin in the neck?

One observation Dobias describes is that dogs repeatedly pulled by the neck may lick their paws, scratch their armpits or use their front legs differently. His proposed explanation involves nerves: cervical injury or nerve irritation can produce altered sensation or pain that appears farther away, for example in the shoulder or foreleg. In people, irritation of nerves in the neck can likewise radiate pain or tingling down an arm. It is a possibility worth considering in a dog when an ordinary skin problem does not explain all the symptoms.

Dobias reports having seen paw licking and lameness decrease in his practice after switching from a collar to a harness and addressing neck problems. That is a clinical observation worth discussing, not automatically dismissing. But a dog that licks its paw does not necessarily have a neck injury. Allergies, parasites, wounds, foreign bodies, joint pain, yeast and bacterial infections are also possibilities. Improvement after changing equipment alone does not establish the mechanism responsible.

For me the practical lesson is to ask another question when paw licking, armpit scratching or unexplained foreleg lameness keeps returning: have we examined not only skin and food, but also the neck, movement and loading from the leash? This matters especially when symptoms began after a strong pull or abrupt stop.

Ear infections and the upper neck: Dobiase observations

Dobias discusses ear scratching and recurrent ear infections in relation to the upper neck, particularly vertebrae C1–C3. He hypothesises that tension and changes in blood flow, lymph flow or what he calls “energy flow” in his integrative framework may affect some dogs’ ears. He describes dogs whose ear problems appeared to improve after switching from a collar to a well-fitting harness.

Observation and explanation must be kept separate. Neck anatomy and circulation are real. The “energy flow” concept belongs to Dobiase integrative model and is not a physiological measure established in the same way. I have not found reliable clinical studies showing that a retractable leash causes chronic ear infections through C1–C3 injury. That does not prove such a connection impossible, but neither does it justify blaming a leash automatically.

Recurring ear problems still require assessment for ear canal inflammation, allergies, anatomical factors, microbes and other causes. Reducing neck loading may be a reasonable, low-risk change alongside that assessment, but it does not replace ear examination or treatment.

Thyroid health: could repeated pressure contribute to hypothyroidism?

One of Dobias’s stronger warnings concerns the thyroid gland. His hypothesis is that repeated pressure on the front of the neck could irritate or injure the thyroid region, trigger inflammation and perhaps contribute in some dogs to an autoimmune process that damages hormone-producing cells. He notes that large dogs pulling strongly can exert substantial force through a collar.

This is a specific proposed mechanism, not proof that retractable leashes cause hypothyroidism. The location of the thyroid and the forces applied to the neck are verifiable; a causal chain from ordinary leash pulling to autoimmune thyroid disease in dogs has not been adequately investigated. A 2026 veterinary review also points to the limited clinical evidence for these proposed connections. Suspected hypothyroidism calls for proper diagnostic testing, not merely a different leash.

That uncertainty does not make Dobias’s warning meaningless to me. If direct pressure on the neck can be avoided, it seems reasonable to ask whether we need it during everyday walks at all. We do not have to claim that collars explain all thyroid disease to make that practical choice.

The vagus nerve, heart and digestion: what connects these organs to the neck?

Dobias also highlights the vagus nerve, or nervus vagus, and other autonomic pathways that run through the neck and help regulate the heart, breathing and digestive tract. His concern is that neck trauma could affect nerve function and thereby influence organs that seem far removed from the neck. His writing has linked neck injury with heart, lung and digestive complaints.

We must avoid a logical leap here. The fact that the vagus nerve passes through the neck and participates in organ function does not prove that ordinary retractable-leash tension causes heart disease or bowel disorders. Serious nerve injury can indeed have important medical effects, but causing specific chronic conditions through leash pulling would require separate evidence. Dobias offers a broad clinical interpretation, not a research-based estimate of risk.

Seizures, jugular veins and pressure inside the skull

Another question Dobias raises concerns pressure on the jugular veins and the circulation of fluid around the brain. He proposes that pressure on the neck could interfere with venous drainage, influence intracranial pressure and contribute to seizures in a predisposed dog. The relationships between pressure, blood flow and the nervous system are real physiology, but they do not establish that this sequence occurs clinically during ordinary retractable-leash use.

Seizures have many causes and should never automatically be attributed to a leash. Dogs with seizures, collapse, sudden loss of balance or severe pain after a neck injury need veterinary assessment. It is worth telling the veterinarian if a powerful leash jerk or sudden stop immediately preceded the symptoms.

What do studies show, and what do they not show?

In a 2020 laboratory study, Carter and colleagues measured the pressure produced by different collars on a simulated dog’s neck. The collars generated significant pressure under pulling and jerking, and none eliminated the possibility of injury in that model. This supports caution about forces applied to the neck. It did not measure long-term thyroid, ear or neurological disease in real dogs or compare the springs of different retractable leashes.

A 2026 review in Frontiers in Veterinary Science likewise separates measurable pressure from chronic health outcomes for which direct clinical data are scarce. The review discusses Dobias’s claims. Its conclusion is not that pressure cannot cause harm, but that the existing evidence is insufficient to reliably quantify the risk, frequency or causation of several proposed diseases.

There are therefore three levels to consider. Mechanical loading from a sudden pull is measurable. Symptoms radiating from the neck and effects on other organs are anatomical possibilities that need individual assessment. The links Dobias describes between retractable leashes and persistent disease are, for now, chiefly his clinical observations and hypotheses. Each merits discussion, but they are not equivalent forms of proof.

The cord, handle and lock can injure people too

The narrow, rapidly moving cord of a retractable leash can wrap around fingers, legs or a dog’s paws. A sudden pull can cause friction burns and cuts. When dogs pass one another, a long line can also entangle another animal or person. These injury mechanisms are credible without claiming a precise incidence.

Another hazard is a dropped handle. A large plastic handle rattling along the ground can frighten a dog. If the dog bolts into bushes or woodland, the line can snag. There is also the mechanical risk that the brake does not work as expected. My experience of two failed locks is among the reasons I will not voluntarily take that risk again.

Other reasons Dobias recommends avoiding retractable leashes

Pressure on the neck is only part of his argument. He also suggests retractable leashes can encourage pulling: a dog learns that moving forward releases more line, while the person continually regulates distance using a button. This does not mean every dog using one will pull, but it can complicate teaching relaxed leash walking.

Length matters too. Several additional metres can allow a dog to reach a road, another dog or something dangerous on the ground before the owner intervenes. The cord or tape may wrap around people, animals or objects. A narrow fast-moving cord can cause serious cuts, and a wider tape does not remove entanglement risks. Leash breakage, brake failure and a handle slipping from the owner’s grasp add to the concerns.

Dobias also discusses stress, a dog being startled by the retracting mechanism or a rattling handle, the habits formed during walks, the reliability of the plastic device and its environmental impact. We need not exaggerate this into a claim that every retractable leash is dangerous at every moment. It is enough to recognise several simultaneous risks requiring a conscious choice.

Do harnesses solve everything?

A well-fitting harness can move some of the load away from the neck, especially for dogs that pull or whose neck or trachea needs protection. But a label saying “ergonomic” does not guarantee a proper fit. If the harness rubs under the armpits, restricts shoulder movement or changes the dog’s gait, the size and design need reviewing.

Nor does a harness automatically make a poorly controlled retractable leash safe. If a long line lets a dog build up speed, abrupt stopping can be uncomfortable for the torso too. I therefore separate two questions: what is the leash attached to, and how is its length controlled?

What should you choose instead?

For everyday walks I prefer a strong fixed-length lead that is comfortable to hold. In places where a dog can safely explore and sniff farther away, a separate long line offers another option. It requires more handling, and on muddy days you really do have to pick it up from the ground. But that is precisely how I know the available length and how to shorten it.

A long leash is not inherently bad, nor is a short one always good. The choice must suit the dog’s behaviour, size and surroundings, as well as the person’s ability to control the situation. Teaching calm leash walking so the dog does not continually pull is a worthwhile topic in its own right.

For me, the greatest value of Dobias’s approach is a question to ask before settling on a single explanation for a symptom or equipment choice: have we noticed how much pressure the dog’s neck receives on each walk? I am not saying it explains every ear infection, paw-licking habit or health problem. I do think it makes sense to remove avoidable risks while keeping an open mind about connections that science has not yet investigated adequately.

In conclusion

I no longer use retractable leashes. That decision reflects my own experiences, mechanically plausible hazards and a desire for better control. It does not mean every person using one harms their dog, or that every claimed long-term health effect has been proved. My advice is simple: look at the leash not only as a convenient accessory but as a safety device. Ask what would happen if your dog suddenly lunged right now.

Sources

• Dr Peter Dobias: Retractable leash injuries
• Dr Peter Dobias: Why you should never use a retractable leash
• Dr Peter Dobias: Throat injuries from leashes
• Dr Peter Dobias: Why I would never attach a leash to a collar
• Dr Peter Dobias: Thyroid disease and collar injuries
• Dr Peter Dobias: Ear infections, Part 2
• Dr Peter Dobias: Epilepsy, Part 1
• Carter et al. 2020: collar pressure
• Ridgway 2026: equipment health review
• Hunter et al.: neck force and pressure
• VCA: Controlling pulling on walks
• VCA: Collar and harness options

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