The objectives of gout medication are to rapidly and effectively relieve and eliminate acute attack symptoms, prevent recurrence of acute arthritis, correct hyperuricemia, promote urate crystal dissolution, and treat other concomitant related diseases. Drug treatment of gout should be carried out according to clinical stages and follow the principle of individualization.
Acute attack period
The acute attack phase of gout refers to the attack of gouty arthritis with redness, swelling and heat pain in the joints. Three types of drugs are commonly used: non-steroidal anti-inflammatory drugs (NSAIDs), colchicine and glucocorticoids, all of which should be used early and in sufficient quantity, and gradually reduced and stopped when they are effective. Acute attacks are not treated with uric acid-lowering therapy, and those who are already taking uric acid-lowering drugs do not need to stop using them during attacks.
Intermittent and chronic period
The indications for the use of uric acid-lowering drugs after the inflammation of the joints in gout has subsided are: recurrence of acute gout, involvement of multiple joints, and the appearance of gout stones. The goal of treatment is to achieve a blood uric acid <6 mg/dl.
The approach is to start with a small dose after the acute attack has subsided for at least 2 weeks, gradually increase the dose, adjust to the minimum effective dose over several months and maintain it for a long time or even for life. Low-dose colchicine or NSAIDs should be taken for at least one month at the same time as the initiation of uric acid-lowering drugs in order to prevent recurrence of acute arthritis.
Drugs that inhibit uric acid production
Inhibits the conversion of hypoxanthine and xanthine into uric acid by inhibiting xanthine oxidase (XO), and is used in patients with excessive uric acid production or those who should not use uric acid excretory drugs. The representative drug is allopurinol.
Uric acid excretory drugs
These drugs inhibit tubular reabsorption and increase uric acid excretion. They are used in patients with reduced uric acid excretion and in patients who are allergic to allopurinol or whose treatment is not effective. Abnormal renal function affects the efficacy of these drugs and should be used with caution in patients with urinary tract stones or chronic uric acid nephropathy, and is contraindicated in patients with acute uric acid nephropathy, who should alkalinize the urine and maintain urine volume. The representative drugs of this class are propofol, benzosulfone, and benzbromarone.
Precautions for uric acid-lowering therapy
Principles of management of asymptomatic hyperuricemia: Non-pharmacological treatment should be the main focus, and the use of uric acid-lowering drugs is generally not recommended. However, in patients whose blood uric acid is still higher than 9 mg/dl after dietary control; with family history or concomitant related diseases whose blood uric acid is higher than 8 mg/dl, uric acid-lowering therapy can be administered.
How to prevent gout attack
The ways to prevent gout attacks during uric acid lowering are as follows.
Make uric acid fluctuation small
Patients who are using uric acid-lowering drugs for the first time use the method of increasing dosage (the faster the uric acid is lowered, the easier it is to have an attack), otherwise the sudden decrease in blood uric acid level will cause the formed crystals to fall off from the synovial membrane of the joint, causing a gout attack and the dissolution of the gout stone surface in the joint, forming insoluble crystals and aggravating the inflammation. If you are using uric acid-lowering drugs, you should not stop uric acid-lowering drugs, but adjust the dose.
Preventive medicine
Colchicine 0.5~0.6 mg once or twice a day, and reduce to once a day according to renal function, drug interactions or tolerance, and use verapamil (which increases colchicine blood concentration by 30%, increases bioavailability by 99% and decreases clearance by 52%) or diltiazem (which increases colchicine blood concentration by 31% and increases bioavailability by 87%). Small doses of colchicine can be used as a prophylactic uric acid-lowering agent to reduce the initial acute attacks of chronic gout.
Diacerein inhibits IL-1 activity; inhibits synovial IL-1 synthesis; inhibits IL-1 receptor expression in chondrocytes, and prevents gout attacks during uric acid lowering, the effect can last for 6 months.
Duration of uric acid lowering
Start uric acid lowering 1~6 weeks after the gout attack is relieved, and maintain uric acid lowering for more than six months for those who have the indication of uric acid lowering and have taken blood uric acid lowering drugs. Uric acid <4 mg/dl helps to dissolve gout stones, and uric acid <6.0 mg/dl can reduce the frequency of gout attacks, decrease the size of gout stones, eliminate crystal storage in synovial fluid, improve renal function, and slow down the progress of existing renal insufficiency.