① Function characteristics
The mechanism of zinc in the treatment of Wilson’s disease is:
1,Zinc can competitively inhibit the absorption of copper in the intestine and increase the excretion of fecal copper.
2,Zinc can induce intestinal and hepatocytes to synthesize metallothionein, which has high affinity with copper, so that most copper is in a non-toxic binding state or excreted with intestinal mucosal cells.
3,Zinc can also detoxify excessive copper in liver and brain.
4, Metallothionein induced by zinc is a potential carboxyl radical scavenger. Zinc can quickly alleviate the clinical symptoms of Wilson’s disease, improve abnormal biochemical indexes and EEG, and eliminate or reduce abnormal brain images. Zinc is a safe and effective drug for the treatment of Wilson’s disease, which has been proved in clinical practice since 1980. It has been recommended as the starting and preferred drug for Wilson’s disease.
② Side effects
1,For gastrointestinal irritation, taking a large dose of zinc sulfate before meals can cause nausea, vomiting and diarrhea, which can be avoided after meals.
2,Abnormal numbness and burning sensation of lips.
3,Zinc can reduce the content of vitamin C in the body.
4,Long term high-dose administration can produce high zinc, affect immune function and iron utilization, and even damage learning and memory function; The increase of zinc (copper) can disorder cholesterol metabolism and cause atherosclerosis, but there is no report of the above-mentioned side effects of high zinc in Wilson’s disease patients treated with zinc for a long time.
③ Usage and dose
1,Zinc sulfate: most commonly used (tablets, capsules and solutions). For adults, 200 ~ 1200mg / D, fasting can avoid food interfering with zinc absorption, and postprandial can reduce gastrointestinal reaction, but bread, fine fiber and food containing a large amount of vegetable acid that affect zinc absorption should be avoided as far as possible; If used with meat to promote zinc absorption, the curative effect of zinc can be improved.
2,Zinc acetate: digestive tract reaction is light. Adult, 25mg / time, 4 times / D, 23:00, 50mg.
3,Zinc gluconate and zinc glycyrrhizinate: there are few gastrointestinal side effects. The copper excretion effect is like zinc sulfate, which is more suitable for the treatment of Wilson’s disease. Zinc gluconate tablets 560mg / time, 3 times / D, after meals.
① Penicillamine: Walshe first proposed and successfully used it in Wilson’s disease in 1956, but the symptoms can be aggravated in the first 6 ~ 8 weeks of treatment, and the improvement of clinical symptoms is slower than that of zinc. There are often allergies (fever, rash, lymph node lesions, thrombocytopenia, leucopenia, severe hemolytic anemia and even aplastic anemia) and autoimmune diseases (immune complex nephropathy, hemolytic anemia, Goodtaste syndrome, thyroiditis, lupus erythematosus syndrome, myasthenia gravis, polymyositis, optic neuritis, etc.), which can also lead to vitamin B6 deficiency, Fetal teratogenesis. Therefore, in recent years, zinc agent is used to replace it. If necessary, low-dose penicillamine can be used together. For adults, 1.0 ~ 3.0g/d and 0.5 ~ 0.75g/d under 10 years old; At the same time, vitamin B6 (30 ~ 50mg / D) was supplemented.
② Dimercaptopropanol (dimercaptopropanol): cuming proposed in 1948 that BAL can be used to treat Wilson’s disease by increasing urinary copper excretion. The disadvantage is that there are only injections, pain at the injection site, side effects such as nausea, vomiting and dizziness, and it is difficult to maintain the negative balance of copper, which has been replaced by other drugs. 3 ~ 5mg / (kg · d), 1 ~ 2 times / D, continuous use for 7 ~ 10 days, intramuscular injection; The drug was stopped for 1 week and repeated for 7 ~ 10 days; In the future, 100 ~ 200mg is injected intramuscularly every 1 ~ 2 weeks according to the needs of the disease.
③ Sodium dimercaptobutyrate (sodium dimercaptobutyrate): less side effects, but can only be administered intravenously. Prepare 5% ~ 10% solution with normal saline for 1.0 ~ 2.0g/d, use it continuously for 5 ~ 10 days, and inject it slowly; Reusable. In recent years, dimercaptosuccinic acid capsules can be taken orally, 4.0g/d for adults and 2.0g/d for children, with a course of treatment of 4 weeks.
④ Triethylenetetramine: it is a strong metal complexing agent with small side effects and expensive price. 1.0g/time, 2 times / D, and the maintenance amount is 400g / time, 3 times / d.
⑤ Sodium Dimercaptopropanesulfonate: the curative effect is not as good as penicillamine. 50% sodium Dimercaptopropanesulfonate 2.5ml/time, 2 times / D, continuous use for 5 days, intramuscular injection, reusable.
⑥ Calcium sodium edetate: it can also be used, but the curative effect is poor. Make copper form insoluble copper sulfide in the intestine and excrete it from the body to inhibit copper absorption. 20 ~ 40mg orally, 3 times / day. Adult 1.2g/d, with small side effects. It is used in patients with severe toxic and side effects of penicillamine, but the drug source is difficult and the price is expensive.