Lidocaine

Lidocaine

Lidocaine has been one of the world's most important medicines since doctors first discovered it. This versatile medication blocks nerve signals that cause pain, which makes it effective against many types of discomfort. It also works as a tertiary amine class Ib antiarrhythmic agent that doctors use mainly for local and topical anaesthesia. The World Health Organisation lists it among its Essential Medicines. 

This article covers everything patients should know about lidocaine. Readers will learn about lidocaine uses, how to take it properly, side effects to watch for, and safety precautions. 

What is Lidocaine?

Lidocaine, an amino amide-type local anaesthetic, blocks nerve signals in your body by preventing sodium ions from entering nerve cell membranes. This remarkable drug is available in many forms like creams, gels, sprays, patches, injections and tablets—each serving a specific purpose.

Your body's pain signals stop reaching the brain when lidocaine numbs the applied areas. The drug starts working within minutes, and its effects last between 30 minutes to three hours. Doctors often combine it with epinephrine to make it last longer and reduce bleeding.

Lidocaine Uses

Doctors prescribe lidocaine to:

• Help with nerve pain after shingles (post-herpetic neuralgia)
• Fix ventricular tachycardia and other heart rhythm problems
• Make areas numb before medical procedures
• Reduce irritation in the mouth and throat

How and When to Use Lidocaine 

Your doctor's instructions should guide your usage. The drug shouldn't touch broken skin or get wrapped tightly. Clean your hands really well before and after use. Heat exposure should be avoided, as it might raise lidocaine levels in your body.

Side Effects of Lidocaine 

Redness and irritation at application sites are the most common side effects. Some serious reactions are 

• Low blood pressure
• Methemoglobinemia can cause blue-coloured skin
• Headache
• Fatigue
• Numbness and tingling sensation
• Seizures
• Severe allergic reactions—you should stop using it right away if you have trouble breathing or notice swelling.

Precautions

• People allergic to amide anaesthetics should stay away from lidocaine. 
• Patients with heart disease, liver problems, or G6PD deficiency need careful dose monitoring. 
• Medical staff should monitor ECG readings during intravenous administration.
• Tell your doctor about all ongoing medications, as lidocaine can interact with numerous medicines.

How Lidocaine Works

Lidocaine acts as a class Ib antiarrhythmic agent that blocks sodium channels. The blockage makes your heart contract more slowly and prevents your nerves from sending pain signals to your brain. Lidocaine reduces sharp burning sensations & helps sensitive skin feel normal again when used to treat nerve pain after shingles.

Can I Take Lidocaine with Other Medicines?

Lidocaine interacts with numerous different drugs. These include but not limited to:

• Acetaminophen
• Bupivacaine
• Chloroquine
• Dapsone
• Dofetilide
• Eliglustat
• Fentanyl
• Fluvoxamine
• Ivabradine
• Mefloquine
• Naloxegol
• Nitrates
• Pefloxacin
• Phenobarbital
• Phenytoin
• Pimozide
• Propranolol
• Sulfonamides

Lidocaine can also interact with certain health conditions like liver problems, kidney issues, and seizure disorders.

Dosing information

Your condition and treatment type determine the dosage:

• For ventricular arrhythmias: 1-1.5 mg/kg intravenously
• For local anaesthesia: 4-4.5 mg/kg maximum
• For children: A doctor must determine the dosage

Doctors usually prescribe lower doses to older adults, people with liver issues, or those with heart problems. Medical staff must monitor patients during administration, especially those with cardiac conditions.

Conclusion

Lidocaine is a remarkable medication that doctors use widely in medical practice. This versatile drug helps countless patients dealing with nerve pain and heart rhythm abnormalities. You can receive it through creams, patches, injections, and tablets. 

Patients should follow their doctor's instructions carefully. Each condition needs specific dosages, so medical supervision matters greatly. People with liver or heart problems and older adults usually need lower doses to avoid complications.

Understanding how lidocaine works helps you make the most of it while keeping the risks down. This key drug has an impact on pain control and heart treatment worldwide. Using it the right way with a doctor's advice gives millions of people big relief and improves life quality.

FAQs

1. Is lidocaine high risk?

Doctors call intravenous lidocaine a "high-risk" medicine. Patients with existing health conditions need extra caution. 

2. Is lidocaine an antibiotic?

No. Lidocaine acts as a local anaesthetic that blocks pain signals. It differs from antibiotics that fight infections by causing temporary numbness in specific areas.

3. How long does lidocaine take to work?

The numbing effects typically start within 30 to 60 minutes. Research shows that substantial anaesthetic effects happen in about 25-30 minutes. You will get the best results between 35-40 minutes after application.

4. What happens if I miss a dose?

Take it once you remember. However, skip the missed dose if it is almost time for your next dose and stick to your regular schedule. Don't try to catch up by taking double doses.

5. What happens if I overdose?

A lidocaine overdose can lead to dizziness, confusion, ringing ears, visual changes, nausea, slurred speech, seizures, and heart problems. Get medical help right away if these symptoms appear.

6. Does lidocaine affect the kidneys?

Lidocaine doesn't directly impact kidney function. Its main metabolite can build up over time, though, which might cause neurological side effects.

7. Who cannot take lidocaine?

You should avoid lidocaine if you have:

• Hypersensitivity to amide anaesthetics
• Stokes-Adams syndrome
• Wolff-Parkinson-White syndrome
• Severe heart blocks

8. When should I take lidocaine?

Your doctor will give you specific instructions. Apply topical treatments as directed before procedures or when pain occurs.

9. How many days to take lidocaine?

Take lidocaine exactly as your doctor prescribes. Treatment length depends on your condition and specific treatment plan.

10. When to stop lidocaine?

You should stop right away if you notice any warning signs. Watch for blue or grey lips/skin, seizures, dizziness, bad headaches, severe tiredness, confusion, anxiety, ringing ears, or slow breathing. Your doctor will stop lidocaine treatment if your ECG shows too much depression of cardiac conductivity.

11. Is it safe to take lidocaine daily?

Medical supervision is required for daily use. You should only use lidocaine when needed. Your doctor needs to watch you closely during intravenous treatment since side effects can develop faster.

12. What is the best time to take lidocaine?

You'll need to apply lidocaine cream 1 hour before procedures like blood draws. Your doctor might want you to use it earlier for minor surgery. Your doctor's timing instructions should always be followed.

13. What to avoid when taking lidocaine?

Avoid:

• Heat sources like heating pads, saunas, or sunbathing because they make your body absorb more medicine
• Plastic wrap over treated areas
• Food and drinks for an hour after mouth/throat application
• Use on large skin areas or broken skin

14. What happens when you stop taking lidocaine?

The numbness goes away slowly as the medicine leaves your body. Research hasn't shown any withdrawal effects.

15. Does lidocaine make you gain weight?

Scientists haven't found any link between lidocaine and weight changes.

16. Who should not take lidocaine?

Lidocaine isn't safe for people with severe heart block, Stokes-Adams syndrome, Wolff-Parkinson-White syndrome, or allergies to amide anaesthetics. You should be careful if you have liver/kidney problems, G6PD deficiency, or methemoglobinemia.

17. Should I take lidocaine before or after meals?

Meal timing usually doesn't matter. You shouldn't eat right after these treatments to avoid choking.