The Longevity of Youth: How Long Do Fillers Last?

Dermal fillers are one of the most powerful tools we have to create a more youthful appearance. As we age, our faces lose volume – both from reabsorption of fat and bone – which creates a hollow, sunken appearance that allows the soft tissues of the face to droop. Dermal filler injections allow us to correct that with a relatively quick and easy treatment, which is what makes them such popular cosmetic treatments. One of the most obvious questions people ask is ‘How long do fillers last?’ which feels like it should have a simple and straightforward answer. If you go with the answer that the filler manufacturers give you, then depending on the type of filler used, the answer is up to two years. However, a fuller answer is more complicated than that, which is what I want to explain in this blog.

Key Takeaways

1. Filler Longevity: Dermal fillers, particularly those made from hyaluronic acid, often last longer than expected, sometimes persisting for years beyond their intended duration.
2. Technological Evolution: The shift from bovine collagen to hyaluronic acid in fillers has led to longer-lasting effects and reduced allergic reactions, enhancing their efficiency and appeal.
3. Optimal Correction Principle: Achieving ‘optimal correction’ with fillers requires careful, gradual treatment, avoiding overfilling to maintain natural results. Post-optimal correction, touch-ups are needed less frequently, often spaced years apart.

Understanding how long fillers last: the history of fillers

I’m sorry to bore you with a topic like history, but I promise it is relevant to understanding the answer properly. When the first generation of fillers appeared on the market in the early 1980s, they were made from bovine collagen – collagen that was taken from cowhide. Because our body recognises the collagen as foreign material, it mounts an immune reaction to remove it, which typically takes around 2 – 4 months to eliminate the foreign collagen. So, the effects of the collagen typically lasted around 2 – 4 months. Because of the immune mechanism by which collagen products were removed, around 5% of patients had an allergic reaction to the product, which meant that everyone had to get a patch test done before having the treatment – which was more expensive and time-consuming for everyone.

In the mid-90s, a Swedish company came up with the idea of using hyaluronic acid as a filler material. They made the hyaluronic acid from a non-animal source by genetically modifying streptococcus bacteria to produce hyaluronic acid that was genetically identical to human hyaluronic acid. Because it was genetically identical to our body’s own hyaluronic acid, it solved the problem of allergic reactions, which meant they had a superior product that did not require a test patch like collagen. They also noticed that hyaluronic acid appeared to last longer than collagen, although that was something that was never really properly studied.

In the early clinical trials, they compared the longevity of hyaluronic acid fillers with the longevity of collagen products, and, perhaps unsurprisingly, the hyaluronic acid products lasted longer. They would do studies for six to nine months, and at the end of that period of time, they would say, ‘Hey, look, the hyaluronic acid is still there at six months, but the collagen was gone at three months’. And so, it became accepted that hyaluronic acid lasted six months. Later, there were more studies that looked at up to a year, then 18 months and finally two years. What researchers have never done, however, is keep following those patients up to see when the filler actually went away. They just get to the end of the study period and say, ‘Hey, patients still have filler, so this is now how long it lasts’. They also assessed the outcome using photographs of patients, which is a pretty subjective tool.

Now, we are seeing more and more anecdotal evidence from MRI scans of fillers lasting much longer than expected – often years and years after the first injection. This is not a bad thing: in fact, it means that the hyaluronic acid dermal fillers are much more efficient and cost-effective than we previously thought. However, it’s important to really understand this so we do not over-treat and cause the dreaded unnatural, overfilled appearance.

How are hyaluronic acid fillers broken down?

Hyaluronic acid is a molecule that we all have present in our skin and in connective tissue. It’s especially prevalent in our eyes and in our joints, and we have some in our skin, too. Our body has this habit of breaking down material to replace it with new material – and hyaluronic acid is one of the molecules that does that. It gets broken down by an enzyme called hyaluronidase, which turns it into small sugar molecules – known as monosaccharides – which get absorbed and expelled from the body via the lymphatic system. Our assumption is that hyaluronic acid fillers get broken down by excess hyaluronidase that our body produces naturally anyway. However, most of the fillers we inject are injected into the fat below the skin – and there is not a whole lot of hyaluronic acid nor hyaluronidase present naturally there. So, how does the filler get broken down? Well, that’s a really good question that none of us really completely understand yet.

Why do I believe fillers last longer than expected?

I’ve been injecting hyaluronic acid fillers for almost two decades now. In our practice, we inject around 5000 – 6000 fillers per year. We have a lot of experience, and we have seen a lot. And one of the things that I’ve seen is that my patients need top up injections much less frequently that expected. In the early days of dermal fillers we used to perform very basic techniques – simply injecting one syringe at a time and the patient would come back every six months and we would do another one syringe. What we were doing back then was under treating, which is why when patients came back every six months we could keep doing more and it would look ok – to a point. I call that point ‘optimal correction’. When you reach the stage of optimal correction, if you keep treating every six months you get the over-filled face. And that is one of the key reasons you see so many people who look over-filled – they got into the habit of doing regular treatments that initially looked good, but they kept going beyond the point of ‘optimal correction’ and got a build up of product that eventually took them to an unnatural place.

You might think ‘well why didn’t they just stop when it got too much’. The answer is that it is very difficult to be objective about your own appearance and because it happens gradually over time, most patients don’t notice that gradual creep from natural to unnatural. That’s why it’s so important that you find a good doctor you trust to keep you away from that point.

Nowadays our understanding of the ageing process is much more sophisticated than it was 20 years ago. We understand the anatomy of the fat and bones much better, and particularly how they change with age and so we can create much more effective filler treatment strategies that don’t just focus on lines and wrinkles but actually look at the changing shape of the face with age. This means that our filler treatments are much more effective. If you are in your 50s and your face has been losing volume for the best part of 30 years, then you are going to need more like 10 to 20mls of filler to reach optimal correction rather than 1 or 2mls. But when you achieve that optimal correction, you need to take your foot off the gas and re-fill very slowly in the future.

For most of my patients who have had had an optimal correction, I don’t see them back (unless they come in for other skin treatments) for 18 – 24 months. At that stage, we use much smaller volumes to simply maintain them where they are.

Amount of filler injected

The amount of filler injected does have an impact on the longevity of the filler. If you inject a very small amount, and spread it over a wide area, then filler seems to break down more quickly. 

Duration of Different Types of Fillers

Hyaluronic acid fillers

Juvederm

Restylane

Calcium hydroxylapatite fillers

There are now a couple of calcium hydroxylapatite filler products on the market. Radiesse, which is calcium hydroxylapatite in a collagen carrier and Harmonica, which is calcium hydroxylapatite in a hyaluonric acid carrier. The advantage of these products is that the calcium hydroxyapatite component causes an inflammatory response that will stimulate collagen production. This means that as well as having a filling effect, these products may also improve the quality of the overlying skin over time. Again, it is said that these products last ‘up to two years’ although this is a bit vague, and there is no concrete answer and so my advise to patients is to review the outcome in 18 – 24 months and decide then what, if any, additional treatment could be helpful. I mainly use these products for lifting the cheeks and jawline, especially when there is skin quality issues and the patient doesn’t want to have laser skin rejuvenation.

Poly-L-lactic acid fillers

Poly-L-Lactic acid is the material that some dissolving stitches are made from. It also causes an inflammatory response that stimulates collagen production, which is the mechanism by which these products create volume. These are promoted as a ‘more natural’ way of adding volume to the face, because it stimulates your own collagen. However, that’s a bit of a marketing gimmick. The biggest issue with these products is that they have a tendency to form lumps. In one large case series, carried out by a very skilled and experienced dermatologist, one in five patients developed lumps or nodules. One in 10 patients had lumps that were visible. One in 100 patients required surgical excision of the lumps. In comparison to other types of dermal fillers used in the face, this is quite a high rate of complication and is the reason we don’t use this in our practice. (Poly-L-Lactic acid might be more useful in other parts of the body). Again, the expected duration of Poly-L-Lactic acid is up to two years, but this is also based on poor evidence and I’ve seen it persist much longer.

Longevity of Fillers in Specific Areas

Cheek fillers

The cheek is one of the most prominent parts of the face to lose volume with age. There is often a lot of focus on the front of the cheek, or the apple of the cheek, when injecting fillers. This is important for some patients, but not all patients. When we assess the cheek, we need to look at it both while resting and smiling. Often, the cheek can look hollow at rest but full-on smiling, and if you add volume to the front of the cheek in this situation, you will create a look that might look nice at rest but over-filled and hamster-like when the patient smiles. When restoring the cheek, we need to assess the whole cheek – which includes the front part of the cheek, the lower cheek and the back of the cheek (the part in front of the ear). When the cheek is restored properly with cheek fillers, the results can be a dramatically more youthful appearance that looks very natural – even on smiling – so long as the treatment plan takes account of the patient’s own unique anatomy.

Lip fillers

Lip fillers are one of the most abused types of filler treatment that put a lot of people off the idea of having filler. The purpose of filler is to restore volume loss or create additional volume in areas of deficiency. However, many people over-fill lips to create a ‘fashion’ look that looks unnatural. Again, lip fillers have a habit of lasting a long time. When we fill the lips, we typically don’t re-fill until at least 2 years after the treatment – and often, it’s longer.

Under-eye fillers

Under-eye fillers are one of the most challenging treatments to perform. Loss of volume from around the eye is a key part of how the eye ages, so restoring volume here is important, but it’s easy to overdo it. One of the key features of hyaluronic acid is that it loves water and draws in water from its environment, so it can expand a little over time. In most parts of the face, if this happens to a small extent, it doesn’t really matter. But under the eye – where the skin and overlying soft tissues are very thin – even a little bit of expansion can be a problem that creates a puffy look under the eye. To avoid this, it’s always best to under-correct slightly, and spread repeat treatments out adequately – it’s usually at least two years between under-eye filler treatment, and often much longer than this. This is another area that you really need to be careful not to over-correct.

Tips to Extend the Lifespan of Fillers

Follow aftercare instructions

Avoid excessive sun exposure

Maintain a healthy lifestyle

Risks and Side Effects of Fillers

Most side effects of filler injections are minor and self-limiting, which means they go away on their own. The injection itself will inevitably cause a little bit of swelling and redness, and it may cause some bruising, which will go away like any normal bruise. Most patients are able to resume normal activities immediately following treatment. If some bruising develops, you can begin using make-up to hide it from the day after treatment.

Common side effects

The most common side effect is called a delayed inflammatory reaction. This happens to about 1 in 1000 filler treatments. This usually happens a number of months following the initial treatment. The filler has already settled, and most patients have forgotten about the treatment. Then, suddenly, the immune system decides that it doesn’t like the filler any more and causes it to turn hard and lumpy. No one truly understands why this happens, although there are lots of theories on it. If it happens, occasionally, it settles itself down within a couple of days without any treatment. If it doesn’t self-resolve, then we need to go ahead and dissolve the filler by injecting an enzyme that breaks it down. Sometimes, we also need to prescribe steroids to reduce the inflammation. Although this can be a distressing experience, it is treatable, although you are at higher risk of this happening again with future treatments if you choose to carry on with more filler treatments in the future.

Serious side effects of dermal fillers

The most serious side effects of filler injections are caused by inadvertently injecting filler into a facial artery. If this happens, the filler can block the blood supply to the tissues, which means nutrients don’t get to the skin and can ultimately result in some of the skin dying – or undergoing a process of necrosis, resulting in permanent scarring. This is a rare side effect, estimated to happen at a rate of around 1 in 100,000. There are a number of steps that we take during the injection process to minimise the chances of this happening: avoiding areas where we know important blood vessels should be, using blunt cannulas where possible and aspirating before injection. Even if all of these safety checks fail, if you see the blockage immediately and treat it quickly by dissolving the filler, you should be able to avoid it progressing to leave a long-term problem. We have never had a case of necrosis in our practice.

Even more rarely, if you get filler into an artery, instead of flowing forward to cause necrosis, it can move backwards in the circulation and block the blood supply to the eye – causing vision loss. This is the most devastating complication of dermal filler treatments. Fortunately, it is extremely rare. There has only been one reported case in the UK from 2012. The doctor involved in that case has spoken openly about what happened, and it seems the problem was caused by using an unusually large sharp needle that wouldn’t be considered standard practice. Most of the cases of vision loss that have been reported around the world seem to come from East Asian countries, which may be due to either anatomic variations that are common in that part of the world or different techniques that are used there. This is the sort of complication that most doctors hope to never see once in their lifetime.

Reversal options for hyaluronic acid fillers

You have two options for the reversal of hyaluronic acid filler. The first is to wait for the filler to break down naturally. This can take a long time and could easily be a number of years. If you are not satisfied with the outcome of your filler treatment, or if you have a complication, you can dissolve the filler by injecting hyaluronidase, an enzyme that breaks hyaluronic acid down. The preparations of hyaluronidase that are available are not licensed for use in breaking down fillers, but it is commonly performed on an ‘off-label’ basis. Sometimes, you need multiple sessions of hyaluronidase to dissolve the filler, especially with the newer filler materials that are more cross-linked and designed to last longer – they are harder to break down. But dissolving injections still offers you a faster way to get rid of the product than waiting for it to happen naturally. The hyaluronidase injections can cause some swelling, and allergy is possible, so not everyone is suitable for repeat treatments.

Conclusion

‘How long do fillers last?’ Seems like it should be an easy question to answer, but unfortunately, the science is a little more complicated. The key in all of this is finding a reputable doctor who not only performs technically excellent injections but you can trust to give you solid advice on your own circumstances and how to get the most out of the treatment without pushing it too far. Although volume loss is an important part of the ageing process, it’s not the only part and not every sign of ageing can be corrected with filler injections. The advice of a good doctor is key to achieving the best outcome.

FAQ’s

What happens when fillers wear off?

As the filler starts to wear off, the signs of volume loss begin to reoccur. Many people are worried that their skin may sag more because it’s been stretched by the filler. This should never happen because the filler should only be used to restore what’s been lost rather than stretching the skin beyond where it was originally. As long as you adhere to this principle of restoration ,you should never have a problem as the filler goes away.

How often do fillers need to be replaced?

Fillers last longer than most people expect. If you choose to have your filler treatments performed in stages, then you may go back regularly for top-up treatments until you reach the point of ‘optimal correction’. When you achieve optimal correction, however, they should be touched up very infrequently. It’s rare to do a touch-up treatment in less than 18 months, and most patients do so every 2 years or more.

Does filler ever fully go away?

It’s impossible to say that filler ever goes away fully. In most cases, yes, it does, eventually – but over a much longer period of time than most people expect. The process of filler breakdown happens much slower than doctors originally thought. If you do not like the results of your filler treatment, then instead of waiting for it to break down naturally, you may want to think about some dissolving injections to break the product down.

Do fillers last longer than Botox?

Yes, fillers generally last much longer than Botox. Botox is a drug that works by relaxing muscles. It typically wears off within 3 – 6 months. Filler injections with modern hyaluronic acid fillers are licensed to last up to a couple of years, although they often persist even longer than this.

Can filler stay in your face for years?

Yes, fillers can stay in your face for years. In fact, filler persisting for years is the norm in most cases. Some hyaluronic acid fillers are licensed to last up to two years now, although they often persist for even longer than this.