What are fillers?

Fillers are injectable products that can add volume, shape or support to tissue. Many fillers used for cosmetic treatments are temporary and contain hyaluronic acid.

A filler works differently from botulinum toxin, often known by the brand name Botox. Filler is injected into or beneath the skin to add or support volume and contours. Botulinum toxin temporarily reduces the activity of particular muscles.

Which treatment may be appropriate depends on the treatment goal, anatomy, medical information and the product being considered. A practitioner should assess these factors during a consultation.

For the complete filler overview, see fillers.

What types of fillers are there?

Not every filler works in the same way. Important differences include the material used, the treatment goal and how the intended effect develops.

Hyaluronic acid fillers

Hyaluronic acid fillers are temporary gel-based fillers. They may be used when the treatment goal involves adding volume, changing contour or providing support in a particular area.

The possible result depends on the product, amount used, treatment area, anatomy and treatment plan.

Biostimulating fillers

Biostimulating fillers are primarily intended to stimulate processes associated with collagen production. Their effect develops differently from a typical hyaluronic acid filler, so the two categories are not interchangeable for every treatment goal.

Read more about biostimulating fillers.

Permanent fillers

Permanent fillers are materials that are not fully broken down by the body and may remain for many years or potentially indefinitely.

They differ substantially from the temporary fillers commonly used for cosmetic treatments. Permanent material also creates different considerations if problems occur later.

Read more about permanent fillers.

What are fillers made from?

The material depends on the type of filler.

Hyaluronic acid is widely used in temporary cosmetic fillers. It is formulated into injectable gels with different characteristics depending on the product.

This means that not every hyaluronic acid filler is the same. Product characteristics can differ, and the choice should take account of the treatment area, intended result and treatment plan.

Other fillers work by stimulating processes associated with collagen production rather than functioning in exactly the same way as a traditional hyaluronic acid gel.

Learn more about hyaluronic acid fillers.

What do fillers do to the face?

Fillers may be used to add volume, support contours or make certain folds and transitions less noticeable.

What a filler can change depends on where it is placed, the product used, the amount injected and the person's anatomy.

Possible treatment goals include:

• supporting the cheekbones or chin;

• adding volume in an area where volume has reduced;

• changing or supporting particular facial contours;

• softening some deeper folds;

• adding volume to areas such as the lips.

Filler does not treat every wrinkle or facial change in the same way. Muscle movement, skin quality, volume distribution and facial anatomy can each affect which approach may be considered.

For a more detailed explanation of the mechanism, read how fillers work.

Where are fillers used?

Fillers are most commonly discussed in relation to facial treatment areas, although the exact area treated depends on the person's anatomy and treatment goal.

Frequently discussed areas include:

• lips;

• chin;

• jawline;

• cheekbones;

• cheeks;

• nose;

• nasolabial folds;

• marionette lines;

• temples;

• under-eye area.

Not every area is appropriate for filler in every person. For example, one person may be considering additional cheekbone support while another may gain little benefit from adding volume in the same area.

Anatomy, the intended change and the limitations of treatment should therefore be assessed before deciding whether filler is appropriate.

For area-specific information, see cheekbone fillers.

Does getting fillers hurt?

A filler treatment can feel uncomfortable. People may notice a needle prick, pressure or a short-lived stinging or burning sensation.

How the treatment feels depends on factors including the treatment area, injection technique and individual sensitivity.

Some filler products contain a local anaesthetic such as lidocaine. Depending on the treatment, another form of local anaesthetic may also be considered.

This does not mean that every filler treatment is painless.

How long does a filler treatment take?

There is no fixed treatment time that applies to every filler appointment.

The time needed can depend on:

• the consultation;

• treatment area;

• number of areas being treated;

• complexity of the assessment;

• treatment plan.

A treatment involving several areas will generally require a different appointment than a limited treatment involving one area.

What is the difference between fillers and Botox?

Fillers and botulinum toxin are both injectable treatments, but they work differently and are used for different treatment goals.

Fillers

Fillers are used to add volume, shape or structural support. They do not work by temporarily reducing muscle activity.

Botulinum toxin

Botulinum toxin temporarily reduces the activity of selected muscles. Botox is one brand of botulinum toxin.

This means filler and botulinum toxin should not be treated as interchangeable treatments.

Skinboosters

Skinboosters are generally focused more on skin characteristics and are not primarily used to create defined contour or localised volume in the same way as a traditional filler.

Profhilo

Profhilo is generally discussed as a treatment focused on skin quality rather than as a traditional contouring filler.

Which treatment category may be relevant depends on the intended treatment goal and individual assessment.

Are fillers safe?

Filler treatment is not risk-free. Temporary injection reactions and less common complications can occur even when treatment is performed carefully.

Temporary reactions can include:

• swelling;

• redness;

• tenderness;

• bruising.

These should be distinguished from less common problems that may require clinical assessment.

Risk can differ according to the product, treatment area, technique, medical history and other individual factors.

A consultation should therefore cover not only the intended result but also relevant risks, limitations, aftercare and what to do if an unexpected problem develops.

Read more about filler side effects.

What rules apply to fillers in the UK?

Filler rules are not identical across every part of the UK, and regulation can depend on the procedure, product and where treatment takes place.

In England, it is illegal to give a cosmetic filler injection to someone under 18 or to make arrangements for that treatment, apart from limited circumstances involving medical approval.

England is also developing a licensing framework for non-surgical cosmetic procedures. The Health and Care Act 2022 gives the government powers to introduce licensing for practitioners and premises, and the government published its consultation response on the proposed framework in August 2025.

There is not one professional registration that automatically tells you how experienced somebody is with filler treatment. When comparing practitioners, consider relevant professional registration where applicable, training, experience with the particular treatment area, consultation quality, aftercare and how complications are managed.

You can review these details when comparing a filler practitioner.

When might fillers not be appropriate?

Not every cosmetic goal or situation requires filler. A practitioner should assess whether treatment is appropriate for the individual circumstances and whether adding filler is likely to address the intended goal.

Relevant medical information can affect this assessment. This may include an active infection or inflammation in the proposed treatment area, allergies, previous filler complications and previous treatments.

Pregnancy and breastfeeding also require specific consideration before an elective cosmetic filler treatment is considered.

Read more about fillers during pregnancy.

When do you see results from fillers?

With fillers that directly add volume, a visible change may be noticeable immediately after treatment.

The first appearance is not necessarily the settled result because temporary swelling, redness or tenderness can affect how the area looks.

Biostimulating fillers work differently, and their intended effect may develop more gradually.

The appropriate time to assess a result therefore depends on the type of filler and the treatment performed.

A visible change immediately after injection also does not guarantee that the final result will exactly match expectations discussed before treatment.

How long do fillers last?

There is no single duration that applies to every filler.

How long the visible effect lasts can vary according to factors including:

• filler type;

• product;

• treatment area;

• amount used;

• individual factors.

Temporary fillers are designed to be gradually broken down rather than remain permanently.

For detailed information about duration, see how long fillers last.

How much do fillers cost in the UK?

Filler prices can differ according to the product, amount used, treatment area, practitioner and clinic.

Price should not be considered on its own. When comparing treatment options, also look at who performs the treatment, what is covered during the consultation, what product is proposed and how follow-up and possible complications are managed.

For current price information and a more detailed explanation of the factors affecting cost, see filler costs.

Can fillers be dissolved?

Some hyaluronic acid fillers can be broken down using hyaluronidase.

Hyaluronidase is an enzyme that breaks down hyaluronic acid. This means it is not a universal solution for every type of filler.

Whether dissolving is appropriate depends on factors including the material used and the reason treatment is being considered.

Dissolving filler is itself a treatment with relevant risks and limitations and should not be presented as an automatic or simple correction.

For more information, see hyaluronidase.

How do you compare filler clinics and practitioners?

Do not compare filler treatment using price or before-and-after photographs alone.

Consider who would perform the treatment, their relevant experience and what happens during the consultation.

Useful points to compare include:

• professional registration where relevant;

• training and experience with the specific filler treatment;

• experience with the treatment area;

• explanation of the proposed product;

• consideration of relevant medical information;

• realistic discussion of possible results and limitations;

• aftercare and follow-up;

• how the clinic responds if a complication is suspected.

Professional registration can provide useful background information where applicable, but registration alone does not show how much experience somebody has with your specific filler treatment.

Injectablesbooking.co.uk helps you compare clinic and practitioner information before deciding whether you want to request a consultation.

For more guidance, see how to choose a filler clinic.

Frequently asked questions about fillers