When does Botox start working, and how long does it last?

How does botulinum toxin work?

Botulinum toxin temporarily reduces the signal travelling from the nerve endings to a muscle. The treated muscle contracts less, and lines caused by facial expressions soften. This does not happen instantly, because the product needs time to bind to the nerve endings and dampen the signal. For the same reason the effect is not permanent: the nerve endings gradually form new connections and muscle movement slowly returns.

The timeline, day by day

1. Treatment day: small bumps and mild redness may appear at the injection points and usually fade quickly. No change in your expressions is expected yet.
2. Days 2–3: most people start to notice the first effects — frowning or raising the brows becomes a little harder.
3. Week 1: the effect becomes more noticeable. You may feel small differences between areas; it is still too early to judge the final result.
4. Days 10–14: the effect has usually fully settled. This is generally the best time for a review and, if needed, small adjustments.
5. Months 3–4: muscle movement gradually starts to return. For some people this happens sooner, for others later.

How long it lasts in different areas

• Forehead, frown lines and crow's feet: on average 3–4 months for most people.
• Masseter (jaw muscle): depending on the muscle, the effect often lasts longer and is assessed over repeated sessions.
• Excessive underarm sweating: the effect usually lasts longer than for expression lines; duration varies from person to person.
• Areas treated with small doses, such as around the mouth: the effect may be shorter.

What affects how long it lasts?

• Dose and technique: the dose, set according to the area and muscle strength, is one of the main factors. Using a higher dose than necessary to make it last longer can, however, lead to an unnatural look.
• Muscle strength: in strong, frequently used muscles the effect may wear off sooner.
• Metabolism and lifestyle: in people who do a lot of intense exercise the effect may seem to wear off sooner, although this is not true for everyone.
• Regular treatment: in some people treated at regular intervals, the effect may seem to last longer as muscle habits change.

If this is your first treatment

At a first treatment, both you and your physician are learning how your muscles respond. That is why it is usually preferred to start with a measured dose and review the result together at the two-week check-up. A small top-up can be done at that point if needed, which also allows the dose and injection points for your next session to be planned more precisely.

In the first few days some people describe a slight heaviness in the forehead or a feeling of being “different”; this usually eases as you get used to the new pattern of movement. The aim is not to freeze the face but to soften unwanted lines while keeping your expression. How much movement you want to keep is a preference worth discussing at your consultation.

If you are travelling to Istanbul for treatment, this timeline matters when you plan your stay. If you cannot stay for the two-week review, it can be done remotely using photos as part of follow-up for international patients. We also cover timing in our guide to the treatment process in Istanbul.

What happens as it wears off?

The effect does not vanish overnight; muscle movement returns gradually over a few weeks. Lines are not expected to become worse than they were before treatment. When to schedule the next treatment depends on your preference and your physician's assessment; repeating treatment in the same area at very short intervals is generally not recommended.

Protecting the result in the first days

• Do not lie down or massage the treated area for the first 4 hours
• Avoid strenuous exercise, saunas and steam rooms for the first 24 hours
• Wait as long as your physician advises before facials or massages that put pressure on the area
• Let your physician know if you notice unexpected asymmetry or a drooping eyelid

Are Botox and fillers the same thing?

No. Botulinum toxin targets lines caused by muscle movement, while fillers are used for volume loss and contour, and their effects last for different lengths of time. For how long fillers last, see how long do fillers last, and for how they are planned, our dermal fillers page. For fine lines that are visible even at rest, botulinum toxin is sometimes planned alongside skin-quality treatments such as a skin booster.

Pregnancy and breastfeeding, certain neuromuscular conditions, active infection in the treatment area and some medications call for caution with botulinum toxin. That is why a health assessment, however brief, is needed before treatment.