Product Overview
Product name
Saiweige Tadalafil Tablets 20mg*8 tablets
Product specifications
20mg*8 tablets
Expiration date
24 months
Main raw materials
The main ingredient is tadalafil. Chemical name: 6-(1, 3-benzodioxolan-5-yl)-2, 3, 6, 7, 12, 12a-hexahydro-2-methyl, (6R, 12aR)-pyrazino[1’2’:1, 6]pyridino[3, 4-b]indole-1, 4-dione. Chemical structure: Molecular formula: C22H19N3O4 Molecular weight: 389.41.
Manufacturer
Changchun Haiyue Pharmaceutical Co., Ltd.
Precautions
Evaluation of erectile dysfunction should include appropriate medical evaluation to determine possible unknown causes, as well as treatment options. Before prescribing, please note: Cardiovascular Because cardiac risk is somewhat associated with sexual activity, physicians should consider the patient's cardiovascular health status. Therefore, treatments for erectile dysfunction, including this product, should not be used in men for whom sexual activity is not recommended due to preexisting cardiovascular conditions. Patients who experience symptoms at the onset of sexual activity should be advised to abstain from sexual activity and seek medical attention immediately. Physicians should discuss with patients what to do if they develop angina requiring nitroglycerin after taking nitrates. For patients taking nitrates, consider giving nitrates only to treat life-threatening conditions and otherwise at least 48 hours after the last dose.Even in this case, nitrates should be given only under close medical supervision and appropriate hemodynamic monitoring. Therefore, patients who develop angina after taking nitrates should seek medical attention immediately (see "Contraindications"). Patients with left ventricular outflow tract obstruction (e.g., aortic stenosis and congenital hypertrophic subaortic stenosis) may be particularly sensitive to the effects of vasodilators, including PDE5 inhibitors. The following cardiovascular disease patient populations were not included in the clinical safety and efficacy trials of this product, so until further information is available, tadalafil tablets are not recommended for the following patients:? Myocardial infarction within at least 90 days? Unstable angina or angina during sexual intercourse? New York Heart Association grade 2 or higher heart failure in the past 6 months? Uncontrolled arrhythmias, hypotension (<90/50 mm Hg) or uncontrolled hypertension (>170/100 mm Hg)? Stroke in the past 6 months Like other PDE5 inhibitors, tadalafil has a mild systemic vasodilator effect that may cause a transient decrease in blood pressure. In a clinical pharmacology study, tadalafil 20 mg caused a mean maximum decrease in supine blood pressure of 1.6/0.8 mm Hg compared to placebo in healthy subjects (see Pharmacology and Toxicology).Although this effect is not a concern for most patients, physicians should carefully consider whether patients with preexisting cardiovascular disease may be adversely affected by the vasodilatory effects of tadalafil before prescribing. Patients with severely impaired autonomic control of blood pressure may be particularly sensitive to the effects of vasodilators, including PDE5 inhibitors. Potential drug interactions with once-daily dosing Physicians should be aware that once-daily dosing produces sustained plasma tadalafil concentrations, which should be considered when evaluating potential interactions with medications (e.g., nitrates, alpha-blockers, antihypertensive drugs, and strong CYP3A4 inhibitors) or with heavy alcohol intake. Guanylate cyclase (GC) stimulators Physicians should discuss with patients the contraindications to the use of any GC stimulator (e.g., riociguat for pulmonary hypertension). Patients should be informed that blood pressure may be lowered to unsafe levels when GC stimulators are used concomitantly with tadalafil. Prolonged erections Prolonged erections exceeding 4 hours and priapism (painful erections lasting more than 6 hours) are rare with this class of medications.If priapism is not treated promptly, it may cause irreversible damage to erectile tissue. Patients with erections lasting more than 4 hours, whether painful or not, should seek emergency medical attention. Caution should be used in patients with factors that predispose to priapism (such as sickle cell anemia, multiple myeloma, or leukemia) or anatomical defects of the penis (such as abnormal curvature, cavernous fibrosis, or Peyronie's disease). Ocular Reactions Physicians should advise patients that if they experience sudden loss of vision in one or both eyes, they should immediately discontinue all phosphodiesterase type 5 (PDE5) inhibitors, including this product, and seek medical attention. Such an event may be a symptom of nonvascular anterior ischemic optic neuropathy (NAION), a rare condition that is a cause of decreased vision, including permanent blindness, and has been reported rarely in all postmarketing PDE5 inhibitors. According to the literature, the annual incidence of NAION in men aged ≥50 years is 2.5-11.8/100,000. An observational crossover case study evaluated the risk of NAION in patients who used PDE5 inhibitors immediately before the onset of NAION (within 5 half-lives) versus those who used PDE5 inhibitors earlier. The results showed that the risk of NAION increased approximately 2-fold, with a risk estimate of 2.15 (95% CI 1.06, 4.34). The results reported in a similar study were consistent with this, with a risk estimate of 2.27 (95% CI 0.99, 5.20). In these studies, other risk factors for NAION (such as optic disc "crowding") may also contribute to the onset of NAION. However, neither the rare post-marketing reports nor the association between PDE5 inhibitors and NAION in these observational studies prove that there is a causal relationship between the use of PD5 inhibitors and NAION (see "Adverse Reactions").Physicians should consider whether the use of PDE5 inhibitors may adversely affect patients with potential risk factors for NAION. People with a history of NAION are at increased risk for another NAION episode. Therefore, PDE5 inhibitors, including tamoxifen, should be used with caution in these patients and should be used only when the benefits are expected to outweigh the risks. People with a low optic cup/disc ratio are also thought to be at higher risk for NAION compared with the general population; however, there is insufficient evidence to support screening for this abnormality in future users of PDE5 inhibitors, including tamoxifen. Patients with inherited retinal degenerations, including retinitis pigmentosa, were not included in clinical trials, and use is not recommended in these patients. Sudden Hearing Loss Physicians should advise patients to stop taking PDE5 inhibitors, including tamoxifen, and seek medical attention immediately if hearing loss or hearing loss occurs suddenly. These events may be accompanied by tinnitus and dizziness and may be temporally related to taking PDE5 inhibitors, including tamoxifen. It is not certain whether these events are directly related to the use of PDE5 inhibitors or other factors (see Adverse Events). Alpha-blockers and antihypertensive drugs Physicians should discuss with patients the possibility that this product may enhance the hypotensive effect of alpha-blockers and antihypertensive drugs (see "Drug Interactions" and "Pharmacology and Toxicology"). PDE5 inhibitors should be used with caution when used concomitantly with alpha-blockers.PDE5 inhibitors, including this product, and alpha-adrenergic blockers are vasodilators with blood pressure-lowering effects. When vasodilators are used together, there is an additive effect on blood pressure. In some patients, the combination of these two drugs can significantly reduce blood pressure (see "Pharmacology and Toxicology" and "Drug Interactions"), which may lead to symptomatic hypotension (such as syncope). The following situations should be considered: ? Patients should be stable on alpha-blocker therapy before using PDE5 inhibitors. Patients who are hemodynamically unstable when using alpha-blockers alone have been shown to be at increased risk of symptomatic hypotension when taking PDE5 inhibitors. ? Patients who are stable on alpha-blocker therapy should start PDE5 inhibitor therapy at the lowest recommended dose. ? Patients who are already taking the optimal dose of PDE5 inhibitors should start alpha-blocker therapy at the lowest dose. While taking PDE5 inhibitors, gradually increasing the dose of alpha-blockers may further reduce blood pressure. ?The safety of co-administration of PED5 inhibitors and alpha-blockers may be affected by other factors, including intravascular volume depletion and other antihypertensive drugs. (See "Dosage and Administration" and "Drug Interactions"). Renal Impairment Take this product as needed for patients with severe renal insufficiency or end-stage renal disease receiving dialysis, limited to 5 mg, not more than once every 72 hours. For patients with moderate renal insufficiency, the starting dose of this product should be 5 mg, not more than once a day, and the maximum dose is limited to 10 mg, not more than once every 48 hours. For patients with mild renal insufficiency, no dose adjustment is required (see "Dosage and Administration"). Once-daily administration is not recommended for patients with severe renal insufficiency because the exposure (AUC) of tadalafil will increase, clinical experience is limited, and dialysis does not affect clearance. Patients with mild or moderate renal insufficiency do not need to adjust the dose (see "Dosage and Administration").Hepatic impairment Take this medicine as needed For patients with mild or moderate hepatic impairment, the dose of this medicine should not exceed 10 mg. There is insufficient information for patients with severe hepatic impairment, so this medicine is not recommended (see "Dosage and Administration"). Once-daily dosing This medicine has not been extensively evaluated for once-daily dosing in patients with mild or moderate hepatic impairment. Therefore, caution should be advised if once-daily dosing is prescribed to these patients. There is insufficient information for patients with severe hepatic impairment, so this medicine is not recommended (see "Dosage and Administration"). Alcoholic patients should be aware that alcohol and PDE5 inhibitors are mild vasodilators. When mild vasodilators are taken together, the hypotensive effects of each may be increased. Therefore, physicians should inform patients that the combination of large amounts of alcohol (e.g., 5 units or more) with this medicine may increase the likelihood of orthostatic signs and symptoms, including increased heart rate, decreased orthostatic blood pressure, dizziness, and headache (see "Dosage and Administration" and "Pharmacology and Toxicology"). Co-administration with strong cytochrome P450 3A4 (CYP3A4) inhibitors. This product is mainly metabolized by CYP3A4 in the liver. For patients taking strong CYP3A4 inhibitors such as ritonavir, ketoconazole and itraconazole, the dose of this product is limited to 10 mg, not more than once every 72 hours (see "Drug Interactions").Patients taking strong CYP3A4 inhibitors and once-daily tadalafil should not take more than 2.5 mg of tadalafil (see Dosage and Administration). Concomitant use with other PDE5 inhibitors or treatments for erectile dysfunction. The safety and efficacy of tadalafil combined with other PDE5 inhibitors or treatments for erectile dysfunction have not been studied. Advise patients not to use tadalafil with other PDE5 inhibitors. Effects on bleeding In vitro studies have demonstrated that tadalafil is a selective inhibitor of PDE5. PDE5 is found in platelets. When tadalafil 20 mg is coadministered with aspirin, it does not delay bleeding relative to aspirin alone. There is no experience with tadalafil in patients with bleeding abnormalities or significant active peptic ulcer disease. Although it does not prolong bleeding time in healthy subjects, patients with bleeding abnormalities or significant active peptic ulcer disease should use the drug with caution and a careful risk-benefit assessment. Counsel patients about sexually transmitted diseases. This product does not protect against sexually transmitted diseases. Advise patients to take protective measures against sexually transmitted diseases, including human immunodeficiency virus (HIV).
