Side Effects of Xylocaine (lidocaine topical)

Xylocaine (lidocaine topical) is a local anesthetic that works by causing temporary numbness/loss of feeling in the skin and mucous membranes. 

Xylocaine is used on the skin to stop itching and pain from certain skin conditions (e.g., scrapes, minor burns, eczema, insect bites) and to treat minor discomfort and itching caused by hemorrhoids and certain other problems of the genital/anal area (e.g., anal fissures, itching around the vagina/rectum).

Some forms of this medication are also used to decrease discomfort or pain during certain medical procedures/exams (e.g., sigmoidoscopy, cystoscopy). 

Common side effects of Xylocaine include

• temporary redness,
• stinging, and
• swelling at the application site.

Serious but rare side effects of Xylocaine include

• slow/shallow breathing,
• slow/irregular heartbeat, and
• seizures.

Drug interactions of Xylocaine, because of an increased risk of developing methemoglobinemia, include

• nitrates/nitrites,
• other local anesthetics,
• antineoplastic agents,
• antibiotics,
• antimalarials,
• anticonvulsants,
• acetaminophen,
• metoclopramide,
• quinine, and
• sulfasalazine. 

During pregnancy, Xylocaine should be used only when clearly needed. Discuss the risks and benefits with your doctor. 

It is unknown if Xylocaine passes into breast milk. Consult your doctor before breastfeeding.

Common side effects of lidocaine are:

• injection site pain,
• feeling lightheaded,
• euphoria,
• shaking,
• low blood pressure,
• drowsiness,
• confusion,
• weakness,
• blurry or double vision, and
• dizziness.

Other important side effects which may be serious include:

• seizures,
• abnormal heart beats,
• slow heart beat,
• heart block,
• severe allergic reactions,
• respiratory arrest, and
• coma.

People allergic to anesthetics similar to lidocaine should not use lidocaine.

Adverse experiences following the administration of lidocaine are similar in nature to those observed with other amide local anesthetic agents. These adverse experiences are, in general, dose-related and may result from high plasma levels caused by excessive dosage or rapid absorption, or may result from a hypersensitivity, idiosyncrasy, or diminished tolerance on the part of the patient. Serious adverse experiences are generally systemic in nature. The following types are those most commonly reported:

There have been rare reports of endotracheal tube occlusion associated with the presence of dried jelly residue in the inner lumen of the tube.

Central Nervous System

CNS manifestations are excitatory and/or depressant and may be characterized by

• lightheadedness,
• nervousness,
• apprehension,
• euphoria,
• confusion,
• dizziness,
• drowsiness,
• tinnitus,
• blurred or double vision,
• vomiting,
• sensations of heat,
• cold or numbness,
• twitching,
• tremors,
• convulsions,
• unconsciousness,
• respiratory depression, and
• arrest.

The excitatory manifestations may be very brief or may not occur at all, in which case the first manifestation of toxicity may be drowsiness merging into unconsciousness and respiratory arrest.

Drowsiness following the administration of lidocaine is usually an early sign of a high blood level of the drug and may occur as a consequence of rapid absorption.

Cardiovascular System

Cardiovascular manifestations are usually depressant and are characterized by bradycardia, hypotension, and cardiovascular collapse, which may lead to cardiac arrest.

Allergic

Allergic reactions are characterized by cutaneous lesions, urticaria, edema, or anaphylactoid reactions. Allergic reactions may occur as a result of sensitivity either to the local anesthetic agent or to other components in the formulation. Allergic reactions as a result of sensitivity to lidocaine are extremely rare and, if they occur, should be managed by conventional means. The detection of sensitivity by skin testing is of doubtful value.

Patients who are administered local anesthetics are at increased risk of developing methemoglobinemia when concurrently exposed to the following drugs, which could include other local anesthetics:

Examples of Drugs Associated with Methemoglobinemia