A Pilot Study of Needle Size and Pain Perception With Botulinum Toxin A Injections

The Effect of Needle Size on Pain Perception in Patients Treated With Botulinum Toxin A Injections

The purpose of this study is to compare the levels of pain resulting from injections of Botox® for wrinkles on the forehead and between the eyes using two different sized needles (32 gauge and 30 gauge needles).

Subjects will be screened, assessed, and randomized to be injected with onabotulinum toxin A using a 30-gauge needle on one side of the face and injected using a 32-gauge needle on the other side during their first clinic visit. This study is a pilot study designed to determine feasibility of these procedures.

Inclusion Criteria:

1. In good health
2. Is a female
3. Is 25-70 years of age
4. Has moderate dynamic forehead/glabellar wrinkles
5. Has willingness and the ability to understand and provide informed consent and communicate with the study staff

Exclusion Criteria:

1. Younger than 25 or older than 70 years of age

2. Pregnant or lactating

3. Is a male

4. Has received the following treatments in the forehead or glabellar region:

   1. botulinum toxin injections in the past 6 months
   2. ablative laser procedure in the past 6 months
   3. radiofrequency device treatment in the past 6 months
   4. ultrasound device treatment in the past 6 months
   5. medium to deep chemical peel in the past 6 months
   6. temporary soft tissue augmentation material in the area to be treated in the past year
   7. semi-permanent soft tissue augmentation material in the area to be treated in the past 2 years
   8. permanent soft tissue augmentation material in the area to be treated

5. Has an active infection in the forehead or glabellar region (excluding mild acne)

6. Is allergic to cow's-milk protein

7. Is allergic to albumin

8. Taking aminoglycoside

9. Is currently using anticoagulation therapy

10. Has a history of bleeding disorders

11. Has a mental illness

12. Unable to understand the protocol or to give informed consent