Nifedipine sustained-release tablets (Ⅰ)

[Pharmacology and Toxicology] Nifedipine is a dihydropyridine calcium antagonist that selectively inhibits the transmembrane transport of calcium ions into myocardial cells and smooth muscle cells, and inhibits the release of calcium ions from intracellular reservoirs without changing the plasma calcium ion concentration. Pharmacological action This product can simultaneously relax the coronary arteries in the normal blood supply area and the ischemic area, antagonize spontaneous or ergonovine-induced coronary artery spasm, increase the delivery of myocardial oxygen in patients with coronary artery spasm, and relieve and prevent coronary artery spasm. It can also inhibit myocardial contraction, reduce myocardial metabolism, and reduce myocardial oxygen consumption. On the other hand, it can relax peripheral resistance vessels, reduce peripheral resistance, reduce systolic and diastolic blood pressure, and reduce cardiac afterload. This product can delay the sinoatrial node function and atrioventricular conduction of isolated hearts; electrophysiological studies of whole animals and humans have not found that this product has the effect of delaying atrioventricular conduction, prolonging the recovery time of the sinoatrial node, and slowing down the sinoatrial node rate. Toxicological action Carcinogenicity, mutagenicity and reproductive toxicity No carcinogenicity. No mutagenicity. High-dose application can reduce the fertility of female mice; can cause teratogenesis; can cause miscarriage (increased drug absorption rate in fetal mice, increased fetal mortality, and decreased survival rate of newborn mice). Pregnant monkeys taking 2/3-2 times the maximum human dose can lead to small placenta and chorionic dysplasia; giving rats 3 times the maximum human dose can cause prolonged pregnancy. [Pharmacokinetics] It reaches a plateau about 6 hours after oral administration, with small fluctuations, and the effect can last for 24 hours. Under fasting conditions, sustained-release preparations can reduce the fluctuation of blood drug concentration. Oral administration of 90 mg has an average blood drug concentration of 115 ng/ml. Its blood drug concentration can be increased by 60% during high-fat meals, the time to peak concentration is prolonged, and there is no significant change in AUC. Compared with ordinary preparations, the relative bioavailability of sustained-release preparations is 86%. In the dose range of 30-180 mg, the blood drug concentration is proportional to the dose. The drug is converted into inactive metabolites in the liver, 60-80% of which are excreted by the kidneys and 20% are excreted with feces. The elimination half-life is about 2 hours. Nifedipine is highly bound to plasma proteins, about 92-98%. In patients with impaired liver and kidney function, the elimination half-life is prolonged and the bioavailability is improved.

Nifedipine.

This product is a capsule, and the contents are brown particles.

1. Hypertension (alone or in combination with other antihypertensive drugs). 2. Angina pectoris: especially variant angina pectoris.

1. Swallow the whole tablet on an empty stomach. Do not chew or break it apart before taking. 2. Start with a small dose. The initial dose is 20 mg/time, and the maximum dose is 60 mg/time, once a day. The maximum daily dose does not exceed 120 mg. 3. The dose of nifedipine should be gradually adjusted depending on the patient's tolerance and control of angina pectoris. The patient's blood pressure needs to be monitored before increasing the dose. If the patient's symptoms are obvious, the dose adjustment period can be shortened according to the patient's response to the drug. 4. No rebound symptoms were observed when the drug was discontinued, but the dose still needs to be gradually reduced, and the patient's condition should be closely observed. 5. The dose of ordinary preparations can be safely replaced with the dose of sustained-release preparations. For example: ordinary preparations 30 mg/time, three times a day, can be replaced with sustained-release preparations 90 mg/time, once a day.

1. Common adverse reactions include peripheral edema (proportional to the dose); headache, etc. 2. Adverse reactions with uncertain relationship to this product: dizziness; nausea; constipation; fatigue; facial flushing and heat sensation. 3. 1%-3% adverse reactions: chest pain; leg pain; paresthesia; vertigo; rash; leg cramps; nosebleed; rhinitis; impotence; frequent urination, etc. 4.1% Adverse reactions: cellulitis; chills; facial edema; neck pain; pelvic pain; atrial fibrillation; bradycardia; cardiac arrest; premature beats; hypotension; palpitations; phlebitis; postural hypotension; tachycardia; anxiety; loss of libido; depression; insomnia; somnolence; pruritus; night sweats; abdominal pain; diarrhea; dry mouth; indigestion; esophagitis; bloating; gastrointestinal bleeding; vomiting; lymphadenopathy; gout; weight loss; arthralgia; arthritis; myalgia; dyspnea; cough; pharyngitis; blurred vision; amblyopia; conjunctivitis; diplopia; kidney stones, etc. 5. Rare adverse reactions: allergic hepatitis; alopecia; anemia; antinuclear antibody-positive arthritis; erythromelalgia; exfoliative dermatitis; fever; gingival hyperplasia; male breast development; leukocytopenia; mood swings; muscle pain; neurasthenia; purpura; tremor; sleep disorders; Stevens-Johnson syndrome; syncope; thrombocytopenia; toxic epidermal fusion necrosis; momentary blindness at peak blood drug concentration; tremor; urticaria, etc.

It is contraindicated in patients allergic to nifedipine.

Precautions for children: Children are prohibited from using. Precautions for pregnancy and lactation: Precautions for pregnant and lactating women are prohibited. Precautions for the elderly: See [Usage and Dosage] or follow the doctor's advice.

1. Combined with nitrates, it can control angina attacks and has good tolerance. 2. Combined with β-receptor blockers, most patients have good tolerance and efficacy for this product, but some patients may induce and aggravate hypotension, heart failure and angina. 3. Combined with digitalis, it may increase the blood digoxin concentration, suggesting that the blood concentration of digoxin should be monitored when using it for the first time, adjusting the dose or stopping this product. 4. Combined with drugs with high protein binding rate, such as dicoumarols, phenytoin sodium, quinidine, quinine, warfarin, etc., the free concentration of these drugs often changes. 5. Combined with cimetidine, the peak plasma concentration of this product increases, pay attention to adjust the dose. 6. When grapefruit juice is taken with this product, the Cmax and AUC of this product increase.

Keep in a light-proof and airtight container.

10mg

Tentative 24 months

Hongyun Pharmaceutical (Yuxi) Co., Ltd.

• Founded in:

  2015-03-20

• Address:

  No. 133, Fuxian Road, High-tech Zone, Yuxi City, Yunnan Province

• Tax NO.:

  91530400329228369M

• Registered Funds:

  87.275259 million yuan

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