部份中文扑热息痛资料（仅供供参考）
药物药理
药效学
本品为乙酰苯胺类解热镇痛药。通过抑制环氧化酶，选择性抑制下丘脑体温调节中枢前列腺素的合成，导致外周血管扩张、出汗而达到解热的作用，其解热作用强度与阿司匹林相似；通过抑制前列腺素等的合成和释放，提高痛阈而起到镇痛作用，属于外周性镇痛药，作用较阿司匹林弱，仅对轻、中度疼痛有效。本品无明显抗炎作用。
药动学
口服后自胃肠道吸收迅速、完全( 在高碳水化合物饮食后服药可能降低吸收)，吸收后在体液中分布均匀，约有 25%与血浆蛋白结合。小量时(血药浓度<60μg/ml)与蛋白结合不明显, 大量或中毒量则结合率较高, 可达43%。该品90～95%在肝脏代谢，主要与葡糖醛酸、硫酸及半胱氨酸结合。中间代谢产物对肝脏有毒性作用。半衰期β一般为1～4小时(平均2小时), 肾功能不全时不变,但在某些肝脏疾患者可能延长, 老年人和新生儿可有所延长, 小儿则有所缩短。口服后0.5～2小时血药浓度可达峰值, 剂量在650mg 以下时血药浓度为5～20μg/ml, 作用持续时间为3～4小时。 哺乳期间妇女服用该品650mg,1～2小时报乳汁中浓度为10～15μg/ml; 半衰期β为1.35～3.5小时。该品主要以与葡糖醛酸结合的形式从肾脏排泄，24 小时内约有3%以原形随尿排出。
适应症状
适用于缓解轻度至中度疼痛，如感冒引起的发热、头痛、关节痛、神经痛以及偏头痛、痛经等。该品因仅能缓解症状，消炎作用无或极微，不能消除关节炎引起的红、肿、活动障碍，故不能用以代替阿司匹林或其他非甾体抗炎药治疗各种类型关节炎。但该品可用于对阿司匹林过敏、不耐受或不适于应用阿司匹林的病例，如水痘、血友病及其他出血性疾病患者（包括应用抗凝治疗的病例），以及消化性溃疡、胃炎等。应用该品时必要时还须同时应用其他疗法解除疼痛或发热的原因。
用法用量
1．成人常用量口服。一次 0.3—0.6g，每 4小时 1次，或每日 4次；一日量不宜超过 2g，疗程为退热一般不超过 3天，为镇痛不宜超过 10天。
2．小儿常用量口服。按体重每次 10—15mg/kg或按体表面积每天 1.5g/平方米，分次服，每4—6小时 1次；12岁以下小儿每 24小时不超过 5次量，疗程不超过 5天。
Panadol扑热息痛（原始片剂）附件：
Panadol Original Paracetamol Tablets 16 Tablets x 12
1. Name of the medicinal product
Panadol Original Tablets
2. Qualitative and quantitative composition
Each tablet contains Paracetamol Ph Eur 500.0 mg
3. Pharmaceutical form
Tablet
White, film-coated capsule shaped tablet with a triangular logo debossed on one side and a break line on the other.
4. Clinical particulars
4.1 Therapeutic indications
Panadol Original Tablets is a mild analgesic and antipyretic, and is recommended for the treatment of most painful and febrile conditions, for example, headache including migraine and tension headaches, toothache, backache, rheumatic and muscle pains, dysmenorrhoea, sore throat, and for relieving the fever, aches and pains of colds and flu. Also recommended for the symptomatic relief of pain due to non-serious arthritis.
4.2 Posology and method of administration
Adults, the elderly, and children aged 16 years and over:
One or two tablets up to four times daily as required.
Children:
Aged 10 - 15 years: One tablet up to four times daily as required.
Not suitable for children under 10 years of age. Children should not be given Panadol Original Tablets for more than 3 days without consulting a doctor.
These doses should not be repeated more frequently than every four hours nor should more than four doses be given in any 24 hour period.
Oral administration only.
4.3 Contraindications
Hypersensitivity to paracetamol or any of the other constituents.
4.4 Special warnings and precautions for use
Care is advised in the administration of paracetamol to patients with renal or hepatic impairment. The hazard of overdose is greater in those with non-cirrhotic alcoholic liver disease.
Do not exceed the stated dose.
Patients should be advised to consult their doctor if their headaches become persistent.
Patients should be advised not to take other paracetamol-containing products concurrently.
Patients should be advised to consult a doctor if they suffer from non-serious arthritis and need to take painkillers every day.
If symptoms persist consult your doctor.
Keep out of the sight and reach of children.
Pack Label:
Immediate medical advice should be sought in the event of an overdose, even if you feel well.
Do not take with any other paracetamol-containing products.
Patient Information Leaflet:
Immediate medical advice should be sought in the event of an overdose, even if you feel well, because of the risk of delayed, serious liver damage.
4.5 Interaction with other medicinal products and other forms of interaction
The speed of absorption of paracetamol may be increased by metoclopramide or domperidone and absorption reduced by colestyramine. The anticoagulant effect of warfarin and other coumarins may be enhanced by prolonged regular daily use of paracetamol with increased risk of bleeding; occasional doses have no significant effect.
4.6 Pregnancy and lactation
Epidemiological studies in human pregnancy have shown no ill effects due to paracetamol used in the recommended dosage, but patients should follow the advice of their doctor regarding its use. Paracetamol is excreted in breast milk but not in a clinically significant amount. Available published data do not contraindicate breast feeding.
4.7 Effects on ability to drive and use machines
None.
4.8 Undesirable effects
Adverse events of paracetamol from historical clinical trial data are both infrequent and from small patient exposure. Accordingly, events reported from extensive post-marketing experience at therapeutic/labelled dose and considered attributable are tabulated below by system class. Due to limited clinical trial data, the frequency of these adverse events is not known (cannot be estimated from available data), but post-marketing experience indicates that adverse reactions to paracetamol are rare and serious reactions are very rare.
Post marketing data
Body System Undesirable effect
Blood and lymphatic system disorders
Thrombocytopenia
Agranulocytosis
Immune system disorders
Anaphylaxis
Cutaneous hypersensitivity reactions including skin rashes, angiodema and Stevens Johnson syndrome/toxic epidermal necrolysis
Respiratory, thoracic and mediastinal disorders
Bronchospasm*
Hepatobiliary disorders
Hepatic dysfunction
* There have been cases of bronchospasm with paracetamol, but these are more likely in asthmatics sensitive to aspirin or other NSAIDs.
Reporting of suspected adverse reactions
Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme at:www.mhra.gov.uk/yellowcard.
4.9 Overdose
Liver damage is possible in adults who have taken 10g or more of paracetamol. Ingestion of 5g or more of paracetamol may lead to liver damage if the patient has risk factors (see below).
Risk factors
If the patient
a, Is on long term treatment with carbamazepine, phenobarbitone, phenytoin, primidone, rifampicin, St John's Wort or other drugs that induce liver enzymes.
Or
b, Regularly consumes ethanol in excess of recommended amounts.
Or
c, Is likely to be glutathione deplete e.g. eating disorders, cystic fibrosis, HIV infection, starvation, cachexia.
Symptoms
Symptoms of paracetamol overdosage in the first 24 hours are pallor, nausea, vomiting, anorexia and abdominal pain. Liver damage may become apparent 12 to 48 hours after ingestion. Abnormalities of glucose metabolism and metabolic acidosis may occur. In severe poisoning, hepatic failure may progress to encephalopathy, haemorrhage, hypoglycaemia, cerebral oedema, and death. Acute renal failure with acute tubular necrosis, strongly suggested by loin pain, haematuria and proteinuria, may develop even in the absence of severe liver damage. Cardiac arrhythmias and pancreatitis have been reported.
Management
Immediate treatment is essential in the management of paracetamol overdose. Despite a lack of significant early symptoms, patients should be referred to hospital urgently for immediate medical attention. Symptoms may be limited to nausea or vomiting and may not reflect the severity of overdose or the risk of organ damage. Management should be in accordance with established treatment guidelines, see BNF overdose section.
Treatment with activated charcoal should be considered if the overdose has been taken within 1 hour. Plasma paracetamol concentration should be measured at 4 hours or later after ingestion (earlier concentrations are unreliable). Treatment with N-acetylcysteine may be used up to 24 hours after ingestion of paracetamol, however, the maximum protective effect is obtained up to 8 hours post-ingestion. The effectiveness of the antidote declines sharply after this time. If required the patient should be given intravenous N-acetylcysteine, in line with the established dosage schedule. If vomiting is not a problem, oral methionine may be a suitable alternative for remote areas, outside hospital. Management of patients who present with serious hepatic dysfunction beyond 24h from ingestion should be discussed with the NPIS or a liver unit.
5. Pharmacological properties
5.1 Pharmacodynamic properties
Paracetamol is an antipyretic analgesic. The mechanism of action is probably similar to that of aspirin and dependant on the inhibition of prostaglandin synthesis. This inhibition appears, however to be on a selective basis.
5.2 Pharmacokinetic properties
Paracetamol is rapidly and almost completely absorbed from the gastrointestinal tract. The concentration in plasma reaches a peak in 30 to 60 minutes and the plasma half-life is 1 - 4 hours after therapeutic doses. Paracetamol is relatively uniformly distributed throughout most body fluids. Binding of the drug to plasma proteins is variable; 20 to 30% may be bound at the concentrations encountered during acute intoxication. Following therapeutic doses 90 - 100% of the drug may be recovered in the urine within the first day. However, practically no paracetamol is excreted unchanged and the bulk is excreted after hepatic conjugation.
5.3 Preclinical safety data
There are no pre-clinical data of relevance to the prescriber which are additional to that already included in other sections of the SPC.
6. Pharmaceutical particulars
6.1 List of excipients
Maize starch, potassium sorbate, purified talc, stearic acid, polyvidone, starch pregelatinised, hypromellose, and triacetin.
6.2 Incompatibilities
None.
6.3 Shelf life
48 months.
6.4 Special precautions for storage
None.
6.5 Nature and contents of container
PVC 250μm / aluminium foil 30μm blister packs in an outer cardboard carton, containing 4, 6, 12 or 16 tablets, or PVC 300 μm/aluminium foil 30 μm blister packs in a cardboard/PVC wallet containing 16 tablets.
6.6 Special precautions for disposal and other handling
Not applicable.
7. Marketing authorisation holder
GlaxoSmithKline Consumer Healthcare (UK) Trading Limited
980 Great West Road
Brentford
Middlesex
TW8 9GS
United Kingdom
8. Marketing authorisation number(s)
PL 44673/0081
9. Date of first authorisation/renewal of the authorisation
29.05.84
10. Date of revision of the text
May 2017