[Product name and structural formula]

Official Name: Terbinafine Hydrochloride Tablets

English name: Terbinafine hydrochloride tablets

Hanyu Pinyin: Binet.Alfred Fen Yan Suate Tablets.

The chemical structural formula is as follows:

【 Description 】 This product is a white or white-like tablet.

[Pharmacology] Terbinafine is an acrylamide drug with broad-spectrum antifungal activity. This product can selectively resist the epoxidation of squalene, so that the epoxidation of squalene is blocked during the formation of fungal cell membrane, thus achieving the effect of killing or resisting fungi.

[Absorption, Distribution and Elimination] According to the literature, the peak blood concentration of terbinafine 250mg was 0.97μg/ml within 2 hours after administration. The absorption half-life of this product is 0.8 hours, and the distribution half-life is 4.6 hours. Its bioavailability is less affected by eating, but there is no need to adjust the dose. The binding rate of the drug with plasma protein is 99%, and it can quickly diffuse through dermis and concentrate in lipophilic skin, reaching a fairly high concentration. Terbinafine can enter the deck a few weeks before treatment. The metabolites after biotransformation of this product have no antifungal activity and are mainly excreted in urine. Its elimination half-life is 17 hours, and there is no accumulation in the body. Its steady-state plasma concentration is not affected by age.

However, the clearance rate of terbinafine in patients with liver and renal insufficiency may decrease, which may lead to the increase of blood drug concentration.

[Indications] This product is suitable for

1. Skin, hair and nail infections caused by Trichophyton rubrum, Trichophyton mentagrophytes, Trichophyton verrucosa, Trichophyton interruptus and Trichophyton purpurea, microsporum canis and Trichophyton floccosum.

2. Various tinea (tinea corporis, tinea cruris, tinea manus, tinea pedis, tinea capitis, etc.). ) and skin yeast infection caused by Candida albicans.

3. Onychomycosis caused by dermatophytes (onychomycosis infection).

【 Usage and Dosage 】 Take orally, 0.25g for adults, once a day, and the course of treatment is as follows:

Treatment course of skin infection: tinea manuum and pedis [interphalangeal type and metatarsal type]: 2 ~ 6 weeks; Tinea corporis and tinea cruris: 2-4 weeks; Cutaneous candidiasis: 2~4 weeks. A few weeks after mycology was cured, the skin appearance was completely normal and the infection symptoms disappeared.

Treatment of hair and scalp infection: tinea capitis: 4 weeks, tinea capitis mostly occurs in children;

For onychomycosis, the course of treatment for most patients is 6 weeks to 3 months, and the course of treatment for young patients can be shortened due to the normal growth of nails, so less than 3 months may be enough except for the thumb (toe) nail. In other cases, the course of treatment usually takes only 3 months. Some patients, especially those with nail infections, may need 6 months or more. Patients with slow nail growth in the first week of treatment may need more than 3 months of treatment. After stopping taking medicine for several months, we can see that the disease surface continues to improve until the appearance of the deck is completely normal, because it takes time for healthy nail tissue to grow.

[Adverse reactions] This product is well tolerated, with mild to moderate side effects, often transient. The most common symptoms are gastrointestinal symptoms (fullness, loss of appetite, nausea, mild abdominal pain and diarrhea) or mild skin reactions (rash, urticaria, etc.). ). There have been individual cases of serious skin reactions (such as Stevens-Johnson syndrome and toxic epidermal necrolysis). If you have a progressive rash, you should stop taking the medicine. Rare taste changes, including loss of taste, can be recovered within a few weeks after drug withdrawal. Very few cases have hepatobiliary insufficiency, whether it is caused by this product has not been confirmed, but if the above situation occurs, this product should be stopped. It is reported that very few patients suffer from neutropenia.

[Contraindications] Terbinafine hydrochloride and other components of this product are allergic to it.

【 Precautions 】 For patients with 1, liver or renal insufficiency (muscle liver clearance rate < ml/min, or serum creatinine > 300ml/l =), the dosage should be reduced by 50%. This product should be kept out of the reach of children.

2. Studies on pregnancy and mammals show that this product has no adverse effects on obese children and fertility. Because the experience of pregnant women in using this product is extremely limited, in principle, pregnant women should not use it unless the possible benefits outweigh any possible dangers. Terbinafine can be excreted through milk, so mothers who take this product orally should not breastfeed.

3. The interaction study proved that terbinafine hardly affected the clearance rate of drugs metabolized by cytochrome P450 enzyme system (such as cyclosporine, K860 or oral contraceptives). However, women who use oral contraceptives should use this product with caution, because very few people may have menstrual disorders and liver drug enzyme inhibitors (such as cimetidine). ) can inhibit their removal. Therefore, if these drugs need to be used in combination, the dosage of this product should be adjusted appropriately.

4. Oral administration of this product is ineffective for tinea versicolor.