Botulinum toxin treatment for watery eyes

This page is for patients considering botulinum toxin injections for excessive tear production. This is also known as gustatory lacrimation.

What is the effect of botulinum toxin?

Injection of botulinum toxin into the lacrimal gland temporarily reduces the excessive production of tears (without damaging the gland) in patients whose eyes water due to abnormal nerve connections. This usually occurs when chewing or eating, and the condition is commonly known as “watery eyes.”

Will botulinum toxin affect my general health?

The treatment is safe and there is no significant risk of developing botulism or food poisoning. This is because it acts locally at the site of injection with minimal to noabsorption into the blood stream. We have never had a patient who has experienced any general health problem due to botulinum, but all medication carries a small potential risk of a serious allergic reaction (anaphylaxis).There is no known risk when the treatment is given to women who are pregnant or breastfeeding, but some patients prefer to postpone treatment until they have given birth or weaned their child. If you are breastfeeding, we strongly advise that you express your milk to use for24-48 hours following the injection.

For further information on the use of botulinum toxin in breastfeeding & pregnancy.

What should I expect when I attend the clinic?

First, your vision will be checked and a general health questionnaire will be given by a nurse or a healthcare assistant. This is because there are some conditions which may notmake you a good candidate for this treatment. You will then be examined by a specialistdoctor. If the treatment is suitable for you, you will be asked to read and sign a consentform, and will usually receive the treatment on the same day. You should expect to be in the clinic for the whole morning or afternoon.

What is the treatment procedure?

You will be given local anaesthetic drops to numb your eye. These drops are very effective in taking away the surface sensation of the eye but you might still experience some discomfort when the injection is given. A small injection is given into the lacrimal (tear) gland, either through the upper lid skin or just underneath the lid by turning the lid over. Usually, neither stitches nor an eye patch is needed.

What happens after the injection?

You will be able to go home after the injection. Youmay feel an ache in the injected area for which for which you can take a painkiller as needed. You also may develop a small bruise, which will usually settle down within a few days.

When should I expect to see results from the treatment?

Results are usually noticeable about two days after the injection is given.

How long do the results last?

This can vary, but results usually last between three and five months.

What are the possible side effects?

With any injection in or around the eye it is possible to suffer a serious side effect affecting the eye or vision, but this is extremely rare.

Nearly all side effects are temporary and recover with time. Potential side effects are as follows:

  • Dry eye: this may need to be treated with artificial tear drops before the effect wears off.
  • Drooping of the eyelid on the injected side.
  • Temporary double vision – you should not drive while you have double vision. It is very important that you discuss this with the doctor before treatment if this is of particular concern to you (see DVLA website: double vision and driving).
  • Slight bruising of the eyelid.

When do I return to the clinic?

We will make an appointment for you to return to the clinic three or four months after your treatment.

Other important information

The majority of medicines used in the UK hold a ‘product licence’ or ‘marketing authorisation’ which is granted by a government organisation. The licence covers specificconditions in which the medicine can be used to treat people. Although botulinum toxin has been used for treating eye conditions at Moorfields since 1982 and has been used for treating watery eyes since 1998, manufacturers have never applied for a drug product licence. We use it on a “named patient” basis, and records are kept of all injections and patient details. This is one of many examples of a drug with a product licence for one condition being used safely and successfully for another condition.

If you have any reason to believe that you may be a carrier of hepatitis or the HIV virus, please make sure that you tell the nurse or doctor who sees you in the clinic. The information is kept confidential, but it is essentialthat we are informed. If you are not clear about any part of this treatment or have any questions, please ask the doctor to explain further.


Authors: Daniel Ezra, consultant, adnexal service and Anna Ginter, adnexal fellow

Revision date: April 2020