Explaining common pediatric antipyretic drugs
Pediatric fever is a self-protective mechanism that mobilizes the systemic immune system to combat the symptoms of disease. The temperature is closely related to the child’s physical condition, nutritional status, time (such as morning and evening, four seasons), but not to the severity of the disease, that is, not the higher the temperature, the more serious the disease, sometimes repeated hyperthermia 3-5 days is very common, so in the process of reducing fever, we should actively look for treatment of the original disease, do not simply focus on reducing fever.
I. When to apply antipyretic drugs?
A fever is defined as a fever when the axillary exceeds 37.3°C (or 37.5°C). It is also divided into low fever 37.4~38°C; medium fever 38.1-39°C; high fever 39.1-41°C; ultra-high fever: 41°C or more. A fever of ≤1 week is an acute fever. For patients with a temperature below 38.5°C, if they are in good spirits, they can suspend the use of antipyretic drugs, and physical cooling is sufficient. For patients with temperatures above 38.5°C, antipyretic drugs need to be applied to reduce energy consumption and avoid complications such as hyperthermia.
Second, the use of commonly used antipyretic drugs in pediatrics
The World Health Organization (WHO) recommends two classic oral antipyretics for pediatric use with high safety: acetaminophen and ibuprofen.
1. Acetaminophen (paracetamol, Tylenol): preferred, for children over 3 months of age. Regular dosage for children: 10-15mg/kg/dose orally, once every 4-6h; less than 5 times every 24h for children aged 3-12 years, for a duration of no more than 5d. Rectal administration has not been recommended in pediatrics. Acetaminophen has a high safety profile at reasonable doses, with occasional nausea, vomiting, sweating, and abdominal pain, and a few cases of dermatitis, granulocytopenia, and thrombocytopenia. Excessive doses can cause liver damage. It is contraindicated in severe hepatic and renal insufficiency. Use with caution in children with liver disease or viral hepatitis, hepatic or renal insufficiency, severe cardiopulmonary disorders, and G-6-PD deficiency. Some compound preparations often contain the ingredient “acetaminophen”, such as aminoglutethimide granules, aminophenflavonamil granules, aminoglutethimide syrup, phenomethimide suspension, etc., but paracetamol and tylenol are single preparations. Be sure to avoid repeated medication when taking.
2. Ibuprofen (Merlin): For children over 6 months of age. Single preparations include Merlin, Fenbuterol, etc. The recommended dosage of ibuprofen for children is 5-10mg/kg every 6 hours, up to 4 times every 24h.
Ibuprofen has a strong antipyretic effect, and the process of reducing fever may cause the body to sweat a lot. Therefore, when using ibuprofen to reduce fever, attention should be paid to whether the child is dehydrated or has insufficient intake, and if necessary, intravenous rehydration can be used. Also, ibuprofen is excreted through the kidneys, so it should be used with caution in patients with poor kidney function. Children with G-6-PD deficiency can use “ibuprofen”.
3.Lysine: It is a compound salt of aspirin and lysine, and its mechanism of action is the same as that of aspirin. It is administered intravenously or intramuscularly to reduce or avoid the occurrence of gastrointestinal reactions, with strong antipyretic effect, fast onset of action and mild effect, and can be used as a common drug to reduce fever in pediatrics. It is used for children who are prone to fever convulsions and cannot be administered orally. However, long-term application may induce the possibility of Richter’s syndrome, and even induce anaphylaxis and severe asthma attacks. Used for intravenous antipyretic, the dose is generally 10-20mg/kg, not more than 4 times in 24 hours, the interval should not be less than 4h.
4, aspirin: the traditional antipyretic and analgesic, the World Health Organization does not recommend aspirin routine use for pediatric antipyretic, suggesting the use of other categories of antipyretic drugs instead. China’s pediatrics has basically not used such drugs for antipyretic, only for the treatment of some special diseases, such as Kawasaki disease, rheumatic fever, juvenile arthritis, etc.
5, diclofenac: a new type of potent anti-inflammatory and analgesic, it exerts its pharmacological effects by inhibiting prostate synthesis, has anti-rheumatic, anti-inflammatory, analgesic and antipyretic effects, analgesic, anti-inflammatory and antipyretic effects are 2 to 2.5 times stronger than indomethacin, 26 to 50 times stronger than aspirin, strong, less adverse reactions, small dose, little individual differences, used for fever caused by various inflammatory diseases. There are views that children under 14 years of age are prohibited.
6, Nimesulide: new non-steroidal anti-inflammatory, analgesic, antipyretic, pharmacological effect is to inhibit cyclooxygenase activity, blocking the biosynthesis of prostaglandin-like substances, leukocyte mediator release and polymorphonuclear leukocyte oxidation reaction, so as to play an antipyretic, anti-inflammatory effect, for fever caused by upper respiratory tract infections, the effect can last 6 to 8 hours. 2011 February media reported a number of fatal cases In May 2011, the State Drug Administration issued a notice to restrict the application of Nimesulide and “prohibit its oral preparation for children under 12 years old”.
Name of antipyretic drugs Dose and method of use Age of application Side effects Remarks
Acetaminophen (paracetamol, Tylenol) 10-15mg/kg/dose, po, q4-6h; not more than 5 times in 24h for children aged 3-12 years, duration of treatment not more than 5d 3 months of age and above Fever reduction preferred; use with caution in children with liver disease or viral hepatitis, liver and kidney insufficiency, severe cardiopulmonary disease, G-6-PD deficiency; prohibited in severe liver and kidney insufficiency Occasional nausea, vomiting, sweating, abdominal pain, etc., a few may appear. Abdominal pain, dermatitis, granulocytopenia, thrombocytopenia, etc. may occur in a few cases. Overdose can cause liver damage High safety
Ibuprofen (Merlin) 5-10mg/kg/dose, po, q6h, up to 4 times per 24h. Can be used for children with G-6-PD deficiency above 6 months of age; use with caution for poor renal function Gastrointestinal adverse reactions Strong antipyretic effect, sweating, pay attention to whether the child is dehydrated, insufficient intake, etc., if necessary, through intravenous rehydration
Lysine (lysine + aspirin) 10-20mg/kg/dose, iv OR im, not more than 4 times in 24 hours, interval not less than 4h
Intravenous or intramuscular injection, commonly used in pediatrics, suitable for children with high fever prone to convulsions and those who cannot be administered orally. Long-term application may induce gray baby syndrome, or even induce anaphylaxis and severe asthma attacks.
Aspirin is only used for the treatment of specific diseases, such as Kawasaki disease, rheumatic fever, juvenile arthritis, etc.
Diclofenac is contraindicated in children under 14 years of age
Nimesulide is contraindicated in children under 12 years of age
Clinical principles of pediatric antipyretics
Infants younger than 3 months of age are not recommended to use antipyretic drugs. Physical cooling or mild-acting herbal medicines can be used to reduce fever. When the body temperature is lower than 38.5℃, antipyretics are generally not used, and physical cooling can be used to reduce fever, except for those with recurrent febrile convulsions. When the body temperature is higher than 38.5℃, safe antipyretic drugs can be used to treat the fever, and acute fever reduction should be avoided, and be alert to possible dehydration and intravenous rehydration if necessary. Super high fever (>41℃) can cause permanent damage to brain cells and even other serious complications such as pulmonary edema, cerebral edema and liver failure, which can lead to death in severe cases, so active and effective resuscitation measures should be used to rapidly lower the temperature.
If a child with persistent high fever does not reduce fever with a single drug, acetaminophen and ibuprofen can be applied alternately. The time interval between the two drugs should be at least 2 hours. When alternating, the maximum number of times each drug can be used is still 4 times a day. Drink more water when taking medication to reduce fever to speed up excretion and help take away body heat. At the same time, it is also necessary to take medicine to reduce fever along with physical means of cooling, which includes taking a warm bath or wiping the whole body with a hot wet towel, and not using alcohol, which can easily pass through children’s tender skin and lead to alcohol poisoning. Avoid the simultaneous use of multiple antipyretic drugs, increasing the risk of side effects.
Fourth, the application of pediatric antipyretic drugs should pay attention to matters
(1) Pediatric thermoregulatory center is not perfect, so pediatric antipyretic should be based on physical cooling.
(2) Fever is a manifestation of the body’s resistance to disease, and the cause should be actively investigated and the primary disease should be treated.
(3) Master the active ingredients, drug action characteristics, adverse reactions, contraindications, and contraindications of various antipyretic and analgesic drugs to prevent damage to the body due to improper use of drugs.
(4) According to the characteristics of pediatric antipyretic drugs, reasonably grasp the interval of pediatric antipyretic drug use.
(5) The dose should be taken on time and in accordance with the dosage, do not arbitrarily increase the dose or shorten the dosing interval.
(6) During the period of fever reduction, the child should be advised to drink more water to avoid deficiency due to profuse sweating.
(7) Generally choose one kind of antipyretic drug, and consider combining it when the efficacy is really unsatisfactory. Check the body temperature about one hour after each dose to judge the effect of antipyretic.
(8) Reasonable control of the use of the course of treatment, the fever is stopped.
(9) The toxic side effects of drugs should be paid attention to during the use of drugs, such as blood picture changes, gastrointestinal reactions, liver and kidney function damage, etc.
(10) If necessary, subhypnotic therapy can be used for children with severe illness and persistent high fever.