Introduction
Topican is a combination of two local anesthetic medicines, that helps to numb the area where it is applied. It is used on normal or unbroken skin to prevent pain before certain procedures like inserting a needle, suturing of a wound etc.
Topican works by temporarily numbing the skin and surrounding area. It should be used in the dose and duration as advised by your doctor. This medicine is for external use only. Make sure that the affected area is clean and dry before applying this medicine. Apply a thin layer and rub it gently to form a layer of about 2-3mm. After that, apply an occlusive dressing to protect the area. Keep the dressing for a minimum of 2 hours before any scheduled treatment or surgery. Avoid getting it into your eyes or mouth. If accidental exposure occurs, rinse thoroughly with water.
The most common side effects of this medicine include application site reactions like a burning sensation, irritation, itching, redness, and rashes. However, these are usually temporary and resolve on their own. Please consult your doctor if these do not go away or bother you for a longer duration.
Uses of Topican
- Local anesthesia (Numb tissues in a specific area)
Side effects of Topican
Common
- Application site reactions (burning, irritation, itching and redness)
- Rash
How to use Topican
This medicine is for external use only. Use it in the dose and duration as advised by your doctor. Check the label for directions before use. Clean and dry the affected area and apply the gel. Wash your hands after applying, unless hands are the affected area.
How Topican works
Topican is a combination of two medicines: Prilocaine and Lidocaine/Lignocaine. It works by blocking pain signals from the nerves of the affected area to t he brain. This decreases the sensation of pain.
Indication
Local anaesthesia
Administration
Apply a thick layer to intact skin and cover with occlusive dressing.
Gently squeeze cream out of the tube as a narrow strip that is 1.5 inches long and 0.2 inches wide; 1 strip corresponds to 1 g
Perform local anesthetic infiltration immediately after removal of cream
Male genital skin: Analgesia will increase up to 3 hours under occlusive dressing and persist 1-2 hours after cream removal
Female genital skin: Occlusive dressing is not necessary but will keep cream in place
Adult Dose
Topical
Dermal Procedures
Minor dermatological procedures (e.g. IV cannulation or venipuncture):
Cream: Apply 2.5 g over 20-25 cm² of skin surface area for at least 1 hr
Painful dermatological procedures involving large areas (eg, split thickness skin graft harvesting)
Cream: Apply 2 g/10 cm² of skin and allow to remain in contact with the skin for at least 2 hr
Analgesia is achieved in 1 hr, reaches maximum in 2-3 hr, and persists 1-2 hr after removal
Topical Anesthetic on Genital Mucous Membranes
Superficial minor surgery on male genitalia and as pretreatment for infiltration anesthesia
Cream: Apply 1 g/10 cm² of skin for 15 min
Minor procedures on the female external genitalia (eg, condylomata acuminata) as well as for use as pretreatment for anesthetic infiltration
Cream: Apply 5-10 g for 5-10 min
Child Dose
Local Anesthetic Procedures
Cream
Neonates (gestation age <37 weeks): Use not recommended
<12 months: Do not use if receiving treatment with methemoglobinemia-inducing agents
0-3 months (or <5 kg): Do not exceed 1 g total dose/application area > 10 cm²/>1 hr application time
3-12 months (and >5 kg): Do not exceed 2 g total dose/application area > 20 cm²/>4 hr application time
1-6 years (and >10 kg): Do not exceed 10 g total dose/application area > 100 cm²/>4 hr application time
7-12 years (and >20 kg): Do not exceed 20 g total dose/application area > 200 cm²/>4 hr application time
Contraindication
Neonates with gestational age <37 wk. Infants <12 mth of age who are receiving treatment with methaemoglobin-inducing agents or children who are receiving medications associated with drug-induced methaemoglobinemia. Children with congenital or idiopathic methaemoglobinemia. Application on mucous membranes, broken or inflamed skin.
Mode of Action
Lidocaine and prilocaine are local anaesthetic agents of the amide type. Both work by stabilising the neuronal membranes and inhibiting the ionic fluxes required for the initiation and conduction of impulses, thereby giving rise to the anaesthetic action.
Precaution
Caution when used over large areas and leaving on for >2 hr. Severe hepatic impairment. Caution when used in patients who are receiving class I and III antiarrhythmics. Dose reduction may be necessary in acutely ill, debilitated patients and elderly. Avoid using on open wounds or near the eyes. Pregnancy and lactation.
Lactation: Excreted in breast milk; use not recommended
Side Effect
>10%
Pallor/blanching (37%),Application site erythema/pain (30%),Genital mucous membrane burning sensation (17%),Oral cavity, periodontal formulation (15%)
1-10%
Alterations in temperature sensations (7%),Application site edema (6-10%),Itching (2%)
<1%
Rash,Myocardial dysfunction (rare),Methemoglobinemia (rare),Depression/excitation (rare),Seizure (rare)
Frequency Not Defined
Localized discrete purpuric or petechial reactions (rare)
Localized hyperpigmentation (rare)
Allergic reactions (eg, urticaria, angioedema, bronchospasm, shock)
Interaction
Increased risk of toxicity when used with drugs that are known to cause methaemoglobinaemia. Concurrent use with class III antiarrhythmics may lead to additive cardiac effects. Toxic effects may be additive when used with class I antiarrhythmics.