Botox aftercare and precautions: before and after the injection

A botulinum toxin injection is a medical procedure, with a before and an after. This page details the precautions set out in the official labels; it complements our page on botulinum toxin and how it works. It does not replace the conversation with your doctor, who is the only one able to assess your situation.

Who should not receive botulinum toxin?

The labels list contraindications, meaning situations in which the toxin must not be used^1,2,3,4:

• a known allergy to botulinum toxin or to one of the product’s ingredients;
• a generalised neuromuscular disease, such as myasthenia gravis or Lambert-Eaton syndrome; one label adds amyotrophic lateral sclerosis³;
• an infection at the planned injection site and, for some labels, inflammation of that area^2,4.

These contraindications apply to type A toxins as well as to the short-acting botulinum toxin (serotype E)^1,4.

What your doctor needs to know before the injection

Your treatments

Mention every medicine you take. Two groups need particular attention:

• anticoagulants and treatments that thin the blood: the toxin should be used with caution in people taking an anticoagulant or who have a clotting disorder². Never stop this treatment on your own: it is up to the doctor who prescribed it to decide;
• certain antibiotics (aminoglycosides) and medicines that act on transmission between nerve and muscle, which can in theory strengthen the effect of the toxin¹.

A recent toxin injection

Say so if you have recently received botulinum toxin, even for another reason and even with another product. Excessive muscle weakness may be made worse by injecting another toxin before the effects of the previous one have worn off¹. The label of the short-acting toxin states that giving it at the same time as another botulinum toxin has not been studied and must be avoided⁴. The units of one product are not interchangeable with those of another^3,4.

Your medical history

Some history matters: a nerve or muscle disease, even one not diagnosed with certainty, difficulty swallowing or aspiration pneumonia, or surgery in the area to be treated¹. People with neuromuscular disorders may be more exposed to serious effects, such as difficulty swallowing or breathing¹. A previous injection that you tolerated badly is also useful information.

Pregnancy and breastfeeding

Botulinum toxin is not recommended during pregnancy, nor in women of childbearing potential not using contraception, nor during breastfeeding^1,4. Data in pregnant women are insufficient^1,4. This topic is covered in our article on what the labels say about botulinum toxin during pregnancy and breastfeeding.

Your age

Use is not recommended under 18^1,3. After 65, trial data are limited; some toxins are not recommended in this age group^1,2. The choice of product takes this into account.

On the day of the injection

As with any injection, pain at the needle site, redness, swelling, slight bleeding or a bruise are possible¹. Pain or anxiety about the needle can cause a brief faint, with a drop in blood pressure¹: mention it if this has happened to you during a blood test or a vaccination.

Remember to ask for the name of the product used and its batch number. The labels require them to be clearly recorded, to ensure the traceability of these biological medicines^1,4. This information will be useful if you change doctor or if an unexpected effect occurs.

After the injection: what advice?

A lot of advice circulates: do not massage, do not exercise, do not lie down, avoid heat or alcohol. The official labels set no quantified waiting time for these situations^1,4. These recommendations come from doctors’ experience; follow the ones your doctor gives you.

A few points, on the other hand, are written in the labels:

• side effects usually appear in the first days and are transient, most often mild to moderate¹;
• the toxin may cause tiredness, muscle weakness, dizziness or visual disturbances that can affect driving¹;
• the effect builds gradually: do not judge the result before the peak effect.

Expected effects and warning signs

Some effects are expected or common: minor reactions at the injection site, headache, a feeling of tightness in the skin¹. Depending on the area, the eyelid or eyebrow may droop; this results from the toxin acting on a neighbouring muscle and is temporary¹.

Other signs, very rare, may reflect spread of the toxin’s effect away from the injection site. The labels ask patients and caregivers to seek immediate medical care in that case^1,4. If you have difficulty swallowing, speaking or breathing, call emergency services straight away (15 or 112 in France, or your local emergency number).

How long should you wait between two sessions?

For type A toxins, the labels require an interval of at least 3 months between two treatments². For the short-acting toxin, the label specifies occasional use; retreatment at intervals shorter than 6 weeks has not been evaluated⁴, and nor has a type A toxin injected less than 30 days afterwards⁴. As of 9 October 2026, this toxin is approved in the European Union (since 15 July 2026) and in Canada (since 22 June 2026), for frown lines only^5,6.

Giving doses too close together or too high may encourage the formation of antibodies, which make the toxin less effective¹. These intervals, and the reasons why the effect wears off, are explained on our page about how long the toxin lasts and how often sessions are spaced. The most common misconceptions are reviewed in our answers to frequently asked questions about botulinum toxin.