Generally speaking, terbinafine is well tolerated, and the adverse reactions are usually mild to moderate. The most common symptoms are gastrointestinal symptoms (fullness, loss of appetite, indigestion, nausea, mild abdominal pain and diarrhea), mild skin reactions (rash, urticaria) and skeletal muscle reactions (joint pain, myalgia).
counteraction
Frequency estimation: very common ≥ (greater than or equal to) 10%, 1%≤ (less than or equal to) common < 10%, 0. 1% ≤ (less than or equal to) uncommon.
Generally speaking, terbinafine is well tolerated, and the adverse reactions are usually mild to moderate. The most common symptoms are gastrointestinal symptoms (fullness, loss of appetite, indigestion, nausea, mild abdominal pain and diarrhea), mild skin reactions (rash, urticaria) and skeletal muscle reactions (joint pain, myalgia).
Unusual: Taste disorders, including loss of taste, can usually be recovered within a few weeks after stopping taking the drug.
Rare: There are reports of hepatobiliary dysfunction (actually primary cholestasis) related to terbinafine treatment, including very rare liver failure.
Very rare: there are reports of serious skin reactions (such as Steven Johnson syndrome and toxic epidermal necrosis) and allergic reactions. If a progressive rash occurs, terbinafine treatment should be terminated.
Very rare: blood diseases such as neutropenia, agranulocytosis or thrombocytopenia have been reported.
Very rare: hair loss has been reported, although the cause has not yet been determined.
Contraindications
It is forbidden to be allergic to terbinafine hydrochloride and other components of this product.
Matters needing attention
If the patient has signs or symptoms of poor liver function, such as unexplained nausea, anorexia or fatigue, or jaundice, black urine or colorless feces, it should be confirmed whether it is hepatogenic and terbinafine treatment should be terminated. A single-dose pharmacokinetic study of patients with existing liver diseases showed that the clearance rate of terbinafine decreased by 50%. Terbinafine is not used in patients with chronic or active liver disease in prospective clinical trials, so it is not recommended.
Patients with impaired renal function (creatinine clearance rate below 50 ml/min or serum creatinine above 300 mmol/L) should take half of the normal dose.
In vitro studies showed that terbinafine inhibited the metabolism of CYP2D6. Therefore, if the therapeutic window of drugs taken at the same time is narrow, patients who receive concomitant treatment with drugs mainly metabolized by this enzyme, such as tricyclic antidepressants (TCAs), β-blockers, selective serotonin reuptake inhibitors (SSRIs) and monoamine oxidase inhibitor B (MAO-IS), should be monitored.
Medication for pregnant and lactating women
Animal experiments on fetal toxicity and fertility show that there are no adverse reactions. Because the clinical experience among pregnant women is very limited, during pregnancy, if the benefits of taking medicine cannot exceed the risks, it should not be used. Terbinafine can be secreted into milk; Therefore, mothers who take terbinafine orally should not breastfeed.
Children's medication
Children over 2 years old are well tolerated by terbinafine.
Medication for elderly patients
There is no evidence that elderly patients and young patients need to take different doses or have different adverse reactions. When prescribing drugs, the possibility of liver and renal function damage in this age group should be considered.
drug interaction
According to the results of in vitro studies and studies on healthy volunteers, terbinafine slightly inhibits or increases the clearance rate of most drugs metabolized by cytochrome P450 system (such as cyclosporine, terfenadine, triazoles, p-toluenesulfonylurea or oral contraceptives).
However, in vitro studies show that terbinafine inhibits CYP2D6-mediated metabolism, which may be related to those compounds that are mainly metabolized by CYP2D6 in clinic, such as tricyclic antidepressants (TCAs), β-blockers, selective serotonin reuptake inhibitors (SSRIs) and monoamine oxidase inhibitors (MAO-IS) type B, because they also have narrow therapeutic windows. It is reported that patients taking terbinafine combined with oral contraceptives have irregular menstruation, although the incidence rate is still within the range of patients taking oral contraceptives alone. On the other hand, some metabolic drugs (such as rifampicin) can accelerate the plasma clearance of terbinafine, while others (such as cimetidine) can inhibit the plasma clearance of terbinafine. If it is necessary to use these drugs simultaneously, the dose of terbinafine should be adjusted accordingly.
excessive
A few cases of drug overdose (up to 5 g) were reported, accompanied by headache, nausea, epigastric pain and dizziness.
The recommended treatment for drug overdose is drug withdrawal, mainly taking activated carbon, and supporting treatment can be given according to symptoms as needed.