Topical Anesthetics for Lentigo

Age: 18+

Sex: Female

Trial Phase: Phase < 1

Sponsor: Northwestern University

Must not be taking: Class I anti-arrhythmics

Disqualifiers: Pregnancy, Male, Kidney disease, others

Compensation: Varies

Number of Visits: 2

Duration: 1 day

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests different topical anesthetics to evaluate their effectiveness in reducing pain during laser treatment for skin spots (lentigines) or sun damage. Participants will receive either lidocaine/prilocaine, lidocaine/tetracaine, or a placebo to compare effects on pain levels. The trial suits females aged 25-65 with noticeable skin spots or sun damage who are interested in laser treatments. Participants should not have had recent skin treatments or any allergies to the anesthetics used. As an Early Phase 1 trial, this research focuses on understanding how the treatment works in people, offering participants the chance to contribute to groundbreaking research.

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking your current medications, but you cannot participate if you are taking a class I anti-arrhythmic medication.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research has shown that lidocaine 2.5%/prilocaine 2.5% cream often numbs the skin before medical procedures. It is generally safe when used as directed, though some individuals might experience skin irritation or an allergic reaction. Serious side effects are rare but can include changes in heart rhythm or a blood condition called methemoglobinemia.

Studies have found that lidocaine 7%/tetracaine 7% cream is also safe and well-tolerated by most people. Common mild side effects include skin redness or swelling at the application site. Serious reactions are uncommon.

Both creams are for use on the skin only and should not be applied to broken skin. Individuals allergic to local anesthetics may find these creams unsuitable. Always consult a healthcare provider if there are concerns about using these creams. ^{1 2 3 4 5}

Why are researchers excited about this trial's treatments?

Researchers are excited about these treatments for lentigo because they offer a potentially more comfortable experience for patients undergoing laser therapy. Unlike standard care options that might not focus on pain mitigation during laser procedures, these topical anesthetics combine lidocaine with either prilocaine or tetracaine to provide targeted pain relief. The use of a topical anesthetic before the laser treatment could make the procedure less painful, improving patient tolerance and potentially leading to better treatment adherence.

What evidence suggests that this trial's treatments could be effective for lentigo?

In this trial, participants will be randomized to receive either lidocaine 2.5%/prilocaine 2.5% cream, lidocaine 7%/tetracaine 7% cream, or a placebo vehicle. Research has shown that lidocaine 2.5%/prilocaine 2.5% cream can significantly reduce discomfort during procedures like chemical peels, providing strong pain relief, especially about an hour after application. However, it may not suffice for managing surgical pain. In contrast, lidocaine 7%/tetracaine 7% cream has effectively reduced pain during skin procedures and is considered safe, offering good pain relief for treatments involving soft tissue. Both creams numb the area to make skin treatments more comfortable. ^{2 6 7 8 9}

Who Is on the Research Team?

Murad Alam, MD

Principal Investigator

Northwestern University

Are You a Good Fit for This Trial?

This trial is for women aged 25-65 with skin types I-III who have moderate lentigines or photodamage and want laser treatment. They must be in good health, able to consent, and not pregnant. Exclusions include certain medical conditions, recent facial treatments, allergies to anesthetics, chronic pain conditions, liver/kidney disease, or tanned skin.

Inclusion Criteria

Females 25-65 years of age

Have Fitzpatrick phototype I-III

You have moderate skin spots and damage from the sun and want to have laser treatment to improve your skin tone.

Exclusion Criteria

Pregnant or lactating

Has G-6-PD and/or pseudocholinesterase deficiency

Has received the following treatments on the face: ablative or non-ablative laser procedure in the past 3 months, radiofrequency device treatment in the past 3 months, ultrasound device treatment in the past 3 months, medium to deep chemical peel in the past 3 months

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

1-2 weeks

Treatment

Participants receive a single pass of the Q-switched 532nm laser after application of topical anesthetics or placebo

1 day

1 visit (in-person)

Follow-up

Participants are monitored for pain perception using a visual analog scale after treatment

1 day

1 visit (in-person)

What Are the Treatments Tested in This Trial?

Interventions

• lidocaine 2.5%/prilocaine 2.5% topical anesthetic
• lidocaine 7%/tetracaine 7% topical anesthetic
• placebo vehicle

Trial Overview The study tests how well different topical anesthetics reduce pain during Q-switched laser treatment for lentigo. It compares lidocaine/prilocaine (LPTA), lidocaine/tetracaine (LTTA), and a placebo. Patients' pain levels are measured after each treated area using a visual scale.

How Is the Trial Designed?

Group I: lidocaine 2.5%/prilocaine 2.5% topical anesthetic Active Control 2 Interventions

Subjects will be screened, assessed, and randomized to be treated with a single pass of the Q-switched 532nm laser after application of LPTA, LTTA, or PV under occlusion to the assigned randomized site.

Group II: lidocaine 7%/tetracaine 7% topical anesthetic Active Control 2 Interventions

Subjects will be screened, assessed, and randomized to be treated with a single pass of the Q-switched 532nm laser after application of LPTA, LTTA, or PV under occlusion to the assigned randomized site.

Group III: placebo vehicle Placebo Group 2 Interventions

Subjects will be screened, assessed, and randomized to be treated with a single pass of the Q-switched 532nm laser after application of LPTA, LTTA, or PV under occlusion to the assigned randomized site.

Who Is Running the Clinical Trial?

Northwestern University

Lead Sponsor

Trials

1,674

Recruited

989,000+

Published Research Related to This Trial

Lidocaine/tetracaine cream (Pliaglis) is a newer topical anesthetic that effectively reduces pain during cosmetic dermatologic procedures, as shown in multiple clinical trials.

This combination anesthetic is favored for its ease of use and mild side effects compared to other topical anesthetics, making it a safe option for patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Review of lidocaine/tetracaine cream as a topical anesthetic for dermatologic laser procedures. Alster, T.[2021]

In a study involving 40 subjects undergoing superficial dermatosurgical procedures, the combination cream of 7% lignocaine and 7% tetracaine provided significantly better pain relief compared to the 2.5% lidocaine and 2.5% prilocaine cream, as measured by visual analogue scale scores.

The findings suggest that the lignocaine/tetracaine combination is an effective topical anesthetic for short-term use (30 minutes), allowing for quicker onset of analgesia and potentially improving the efficiency of dermatological procedures.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Comparison of Topical Anesthetics for Radiofrequency Ablation of Achrocordons: Eutectic Mixture of Lignocaine/Prilocaine versus Lidocaine/Tetracaine. Gahalaut, P., Mishra, N., Chauhan, S., et al.[2021]

A topical gel containing 2.5% lidocaine and 3.5% prilocaine significantly reduced discomfort during 35% trichloroacetic acid (TCA) peels, with 8 out of 10 patients reporting at least a 40% decrease in pain compared to previous peels without anesthesia.

While effective in pain reduction, the gel may increase the depth of the peel, suggesting it should only be used with TCA concentrations below 30% to avoid potential complications.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The efficacy of a topical lidocaine/prilocaine anesthetic gel in 35% trichloroacetic acid peels. Rubin, MG.[2019]

Citations

1. withpower.com withpower.com/trial/phase-lentigo-3-2015-8a36a

Topical Anesthetics for Lentigo · Info for Participants A topical gel containing 2.5% lidocaine and 3.5% prilocaine significantly reduced discomfort during 35% trichloroacetic acid (TCA) peels, with 8 out of 10 ...

2. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC5436754/

Effectiveness of various formulations of local anesthetics ... With lidocaine/prilocaine cream, the strongest analgesic effect is achieved 45–60 min after application;7 among preterm infants and newborns, ...

3. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC4645143/

Comparative Efficacy and Patient Preference of Topical ... Our objective was to compare the efficacy and patient preference of three commonly used topical anaesthetics: (2.5% lidocaine/2.5% prilocaine cream (EMLA®), 4% ...

4. accessdata.fda.gov accessdata.fda.gov/drugsatfda_docs/label/2018/019941s021lbl.pdf

EMLA CREAM (lidocaine 2.5% and Prilocaine 2.5%) The data from 121 patients demonstrated that EMLA Cream was not effective as a sole anesthetic agent in managing the pain from the surgical procedure. The ...

5. bmcgeriatr.biomedcentral.com bmcgeriatr.biomedcentral.com/articles/10.1186/s12877-020-01567-y

Effectiveness of lidocaine/prilocaine cream on cardiovascular ... In older patients, coughing and cardiovascular reactions under anesthesia and endotracheal intubations were reduced, as a result of using lidocaine/prilocaine ...

6. imgcdn.mckesson.com imgcdn.mckesson.com/CumulusWeb/Click_and_learn/SDS_9AKORN_LIDOCAINE_AND_PRILOCAINE_CREAM.pdf

SDS: Lidocaine 2.5% and Prilocaine 2.5% Cream In case of accident, avoid contact with skin and eyes. Other Health Warnings: For topical use only. Notes to Physician: Treat supportively and symptomatically.

7. mayoclinic.org mayoclinic.org/drugs-supplements/lidocaine-and-prilocaine-topical-application-route/description/drg-20062126

Lidocaine and prilocaine (topical application route) Lidocaine and prilocaine topical cream is used on the skin or in the genital area to cause numbness or loss of feeling before certain medical procedures.

8. imgcdn.mckesson.com imgcdn.mckesson.com/CumulusWeb/Click_and_learn/SDS_9EFGRA_0168035730_0168035755_0168035756_LIDOCAINE_AND_PRILOCAINE_CREAM.pdf

Material Safety Data Sheet Systemic adverse effects of Lidocaine and/or Prilocaine are similar in nature to those observed with other amide local anesthetic agents ...

9. goodrx.com goodrx.com/lidocaine-prilocaine/what-is?srsltid=AfmBOoolVe0cnuLiaMMRiWJI_UvZUJsQcbONvdqICmZf08cahPYZN9UO

Lidocaine/prilocaine: Uses, Side Effects, Dosage & Reviews What are the risks and warnings for Lidocaine/prilocaine? · Overdose · Changes in heart rate or rhythm · Methemoglobinemia (a blood condition) · Not for use in ears.