Wrinkle-relaxing injections are widely used to soften lines and create a more relaxed, refreshed appearance

Despite their popularity, many patients are unsure how they actually work. A clear understanding of the mechanism helps patients make informed decisions and set realistic expectations.

What Causes Wrinkles in the First Place?

Not all wrinkles are the same.

Many of the lines that develop on the face, particularly on the forehead and around the eyes, are caused by repeated muscle movement over time.

These are known as dynamic lines, and they form as a result of:

Frowning
Raising the eyebrows
Smiling or squinting

As the skin becomes less elastic with age, these lines can become more noticeable and eventually persist even at rest.

The Role of Facial Muscles

Facial expressions are created by small muscles beneath the skin. Each time these muscles contract, they pull on the skin above them. Over time, this repeated movement leads to the formation of lines.

Wrinkle-relaxing injections work by temporarily reducing the activity of these specific muscles, rather than treating the skin directly.

When these muscles contract, they pull on the skin above them. Over time, this repeated movement leads to the formation of lines.

How Wrinkle-Relaxing Injections Affect Muscle Activity

The treatment works by interfering with the communication between nerves and muscles.

In simple terms:

Nerves normally send signals to muscles to contract
Wrinkle-relaxing injections reduce the strength of this signal
The targeted muscle becomes less active

This results in:

Reduced movement in the treated area
Softening of existing lines
Prevention of lines becoming more deeply established

For a broader overview of treatment options, see our guide to wrinkle-relaxing injections

What Happens After Treatment?

The effects are not immediate.

Typically:

Initial changes begin within a few days
Full effect develops over 1–2 weeks
Results gradually wear off over time

As muscle activity returns, lines may slowly reappear, which is why treatment is usually repeated at intervals.

If you are unsure how often treatment is needed, this is discussed in more detail in our upcoming guide to treatment frequency.

Does It Affect Natural Expression?

A common concern is that wrinkle-relaxing injections will make the face look “frozen”. This is explored further in our discussion on the so-called frozen look

When performed appropriately, the aim is not to eliminate movement completely, but to:

Soften excessive muscle activity
Maintain natural expression
Avoid an over-treated appearance

Unnatural results are usually related to technique or dosing, rather than the treatment itself.

How Is This Different from Other Treatments?

Wrinkle-relaxing injections target muscle movement, whereas other treatments work in different ways.

For example:

Treatments that improve skin quality focus on hydration and collagen
Volume-based treatments restore structure or contour

This is why wrinkle-relaxing injections are often used alongside treatments such as natural-looking dermal fillers, rather than replacing them.

Are They Safe?

When performed by appropriately trained practitioners, wrinkle-relaxing injections have a well-established safety profile.

However, as with all medical treatments, there are potential risks.

Patients often have questions about terminology and safety, which are addressed in is botulinum toxin safe?

A full discussion of risks and suitability should always take place during consultation.

The Importance of a Proper Assessment

Not all lines require treatment, and not all patients are suitable candidates.

A thorough assessment allows the practitioner to:

Identify the cause of lines
Determine whether treatment is appropriate
Plan treatment carefully

This is why understanding why a consultation matters more than the treatment is so important.

Conclusion: A Targeted and Effective Approach

Wrinkle-relaxing injections work by addressing one of the key causes of facial lines — muscle activity.

By reducing excessive movement in specific areas, they can:

Soften existing lines
Prevent deeper lines from forming
Maintain a natural appearance when used appropriately

As part of a considered and individualised treatment plan, they remain a precise and effective option in aesthetic medicine.

Considering treatment

A consultation allows you to explore your concerns and make a fully informed decision without pressure.

You can read more about what happens during an initial consultation.

Arrange a consultation

To make a booking with one of our doctors please use the links below to telephone or email or to fill out our contact form click here.

How Do Wrinkle-Relaxing Injections Work? A Straightforward Explanation