Terbinafine: Overview, Uses and Side Effects

Oral terbinafine is systemic, meaning it is absorbed into the bloodstream and reaches different parts of the body, providing a more comprehensive approach for treating fungal infections that extend beyond the skin's surface.Terbinafine tablets can be prescribed for adults and children aged 1 year and over. Your doctor may recommend tablets if they think creams, gels, sprays or solutions are not likely to work on the fungal infection. You should only go see your doctor about terbinafine if:

Severe Infection

For severe or persistent fungal nail infections, especially those affecting multiple nails or with associated complications, seeking professional medical advice is essential. Severe infections include when TWO OR MORE nails are affected.

Previous Treatment Failures

If you've previously attempted over-the-counter antifungal treatments or home remedies without success, it's time to consult your GP. They can evaluate the reasons for treatment failure and recommend a more effective strategy, which may include prescription-strength antifungals like terbinafine.

Medical History

Your doctor will assess your medical history, including any existing health conditions, allergies, and medications you're taking. If you are diabetic, there may be an underlying cause, which is why the NHS recommends all diabetics to have regular eye and foot checks. This applies to certain immunocompromising medical conditions as well.

Pregnancy or Breastfeeding

If you are pregnant, trying to conceive, or breastfeeding, it's essential to inform your GP. Terbinafine's safety during pregnancy and lactation should be discussed, and alternative treatment options may be considered. They will run through the most suitable option for you.

Liver or Kidney Issues

Individuals with a history of liver or kidney problems should inform their doctor before starting terbinafine. Adjustments to the dosage or consideration of alternative treatments may be necessary.

Types of Terbinafine formulations

Topical Formulations

A breakdown of uses of topical terbinafine

• Skin Infections (Athlete's Foot, Ringworm, Jock Itch) - Terbinafine creams, gels, or solutions are often used for superficial fungal infections on the skin. They are applied directly to the affected area.

• Scalp Infections (Scalp Ringworm) - In some cases, a medicated shampoo containing terbinafine may be recommended for fungal infections of the scalp.

Topical formulations are generally suitable for superficial infections where the fungus is localised to the outer layers of the skin. They are convenient for use on the skin's surface but may not penetrate deeply enough for more severe or persistent infections.

Oral Medication

Here are conditions where oral medications are more commonly used:

• Nail Infections (Onychomycosis): Oral terbinafine tablets are commonly prescribed for fungal infections of the toenails or fingernails, especially when more than one nail has been infected. These infections often require a systemic treatment to reach the deeper layers of the nail where the fungus resides.

• Severe or Extensive Skin Infections: In cases where the fungal infection is extensive, has not responded to topical treatments, or affects areas that are difficult to treat with topical agents, oral terbinafine may be considered.

Pre-treatment

They will also require blood tests before you start treatment and at regular intervals (3-6 months) during treatment to ensure the patient does not experience liver toxicity. Here are the required tests:

1. Liver Function Tests (LFTs): Terbinafine is metabolised by the liver, and in rare cases, it has been associated with liver function abnormalities. As a precaution, doctors may order liver function tests, including measures like alanine aminotransferase (ALT) and aspartate aminotransferase (AST), to evaluate the health of the liver. If a person has a history of liver problems, regular monitoring may be recommended during terbinafine treatment.

2. Full Blood Count (FBC): Although not commonly required for terbinafine, a full blood count might be considered to check for any abnormalities in red blood cells, white blood cells, and platelets.

How to take

Here are our 7 top tips when taking Terbinafine:

1. Follow dosage: Take terbinafine exactly as prescribed by your GP. Do not adjust the dosage or stop the medication without consulting them first. Completing the full course of treatment is essential for effectively eradicating the fungal infection.

2. Be patient: Fungal infections often take time to resolve (up to 6 months). It's important to be patient and continue the treatment as prescribed, even if you start to see improvement. Stopping the medication prematurely could allow the infection to return.

3. Practice good hygiene: Keep the affected area clean and dry. Wash regularly and pat the area dry, especially before applying any topical terbinafine. Avoid sharing towels, socks, or other personal items to prevent the spread of the infection. For fungal infections on the feet, opt for breathable footwear made of materials like cotton. This helps in keeping the feet dry, creating an environment less conducive to fungal growth.

4. Monitor for side fffects: While terbinafine is generally well-tolerated, be vigilant for any unusual symptoms or side effects. If you experience severe side effects, such as liver-related issues (yellowing of the skin, dark urine), notify your healthcare provider promptly.

5. Avoid alcohol: It's advisable to limit or avoid alcohol consumption while taking terbinafine, as the medication is processed by the liver, and alcohol may affect liver function.

6. Regular bloods: Attend any scheduled follow-up blood check ups with your GP to ensure you get your medication on time. This allows them to monitor your progress and submit a prescription request before you run out.

   THEY WILL NOT ISSUE A NEW PRESCRIPTION IF A BLOOD TEST IS REQUIRED AND HAS NOT BEEN COMPLETED.

7. Prevent recurrence: After successfully treating the fungal infection, take steps to prevent recurrence. Maintain good hygiene practices, keep the skin dry, and avoid known sources of reinfection.

To make sure terbinafine is safe for you, tell your doctor or pharmacist if you:

• Have had an allergic reaction to terbinafine or any other medicines in the past

• Have ever had liver or kidney problems as the terbinafine might not be the most appropriate treatment for you or the dose may need to be reduced

• If you are pregnant, trying to get pregnant or are breastfeeding.

How does Terbinafine work?

Terbinafine works by killing the fungus which treats the infection and symptoms. For nail infections treatment usually lasts for between 6 weeks and 3 months, although some patients with toenail infections may need to be treated for much longer.

To make sure terbinafine is safe for you, tell your doctor or pharmacist if you:

• Have had an allergic reaction to terbinafine or any other medicines in the past

• Have ever had liver or kidney problems as the terbinafine might not be the most appropriate treatment for you or the dose may need to be reduced

• If you are pregnant, trying to get pregnant or are breastfeeding.

The most common side effects of terbinafine tablets are having a smaller appetite than usual, pain in your joints or muscles, or an upset stomach. Some people have reported feeling dizzy or giddy while they are taking terbinafine tablets.

Stop taking them and call a doctor immediately if you are experiencing serious side effects; yellow skin or the whites of your eyes turn yellow, you bruise more easily, have a high temperature with a rash, experience severe pain near the top of your stomach that spreads to your back, or if your muscles feel weak or painful, or your pee changes colour to a dark red-brown.