The active ingredient of Eugenol is levothyroxine (L-T4), which has a clear content and good efficacy and is mainly used for the supplementation and replacement therapy of hypothyroidism caused by various reasons. However, because clinicians and patients do not know enough about eugenol and do not know how to take it, they often mistakenly think that eugenol is “ineffective”, resulting in poor control of the disease. Due to the increasing prevalence of thyroid disease, doctors are using Eugenol more and more frequently. Many people ask why the instructions recommend taking Eugenol in the morning on an empty stomach. Sometimes even though we think the dose of Eugenol is sufficient, the patient’s TSH level is still not effectively controlled? In the end, we do not know enough about Eugenol. In fact, there are many reasons that can affect the absorption of Eugenol and lead to the decrease of its drug concentration. As we all know, for papillary thyroid cancer, TSH suppression therapy is a very important tool. However, clinically, it is found that some patients have taken a lot of Eugenol, but the TSH level is still not well suppressed. Is it related to the lack of deiodinase in some patients, as other experts said? A little bit of insight summarized about taking medication for your study and correction: 1.Discerning the authenticity of Eugenol, tell patients to buy it in the regular hospital, do not lose a lot because of small. 2, the correct storage before a patient with hypothyroidism long-term treatment of eugenol, the disease is very well controlled, but in the summer its thyroid function indicators fluctuate greatly. After repeated inquiries, it was discovered that he did not put the medication in the refrigerator, but put it in his bedroom, and the high temperature caused the medication to fail and deteriorate. Therefore, we should inform the patient to store the medication according to the instructions: refrigerated below 25°C. Because of its long half-life (about 7 days), it can be taken only once a day to obtain a stable blood concentration. Because the absorption of Eugenol may be affected by taking it with food, the recommended time to take Eugenol is early in the morning on an empty stomach if possible, with breakfast 30 minutes after taking the medication, and some studies have reported that eating 60 minutes after taking it is optimal. This is because taking it with food may interfere with the absorption of Eugenol. If the dose of the drug is slightly larger, it can also be taken in two doses, early in the morning on an empty stomach before bedtime (3 hours after dinner). Some people may ask: Why is it not routinely recommended to take the medication before bedtime? Because taking the medication early in the morning is more in line with the circadian rhythmical changes of thyroid hormones. Generally speaking, it peaks 5-6h after taking eugenol, so if you take it at night and it peaks around 3am, your heart will be so excited that it will make your heart skip a beat, so do you want to sleep happily? But in everyday life, medication compliance is also an issue that needs to be considered. Nowadays, many young people wake up very late, but need to solve breakfast before going to work, in this case, taking the medication before bedtime may be the best choice. Many studies have found that some diets may affect the absorption of Eugenol, such as grapefruit, soy, strong coffee, milk and high-fiber diets, so avoid taking it with such foods. After informing him about the effect of soy milk on the drug, he never drank it in the morning again and his thyroid function indicators were normalized. This is why Prof. Guan prompted to ask the patient if he drank soy milk and milk after taking Eugenol. Tips: Take Eugenol with plain water and do not eat any food within half an hour. Tips: Eugenol should be taken 4-5h before taking Eugenol and Clofibrate. Drugs containing aluminum, iron and calcium: such as the gastric mucosa protector aluminum thioglycollate, antacid aluminum hydroxide, calcium tablets, etc., can complex with L-T4 in the intestine and prevent its absorption. Tips: Eugenol should be taken at least 2h before taking the above drugs. Drugs affecting the PH value of gastric juice: H2 receptor blockers and proton pump inhibitors affect the PH value by inhibiting gastric acid secretion, hindering its absorption. tips: eugenol should be taken at least 4h before taking the above drugs. 6.Diseases affecting the absorption of Eugenol such as celiac disease, liver cirrhosis, gastric acid deficiency and other absorption disorder syndromes. In addition, some people have lactose intolerance, such as milk intolerance, etc.: because Eugenol contains lactose, this part of patients may be intolerant to Eugenol. 7. drugs affecting the clearance of eugenol Since L-T4 is mainly metabolized in the liver, any drugs with liver enzyme-inducing effects, such as barbiturates, phenytoin sodium, carbamazepine, rifampin, etc., will accelerate the metabolism of L-T4 and increase the hepatic clearance, resulting in a shorter duration of action in the body and a decrease in blood concentration. tips: patients taking these drugs at the same time need to increase the dosage of eugenol. Replenishing thyroid hormones and re-establishing the balance of the hypothalamic-pituitary-thyroid axis generally takes 4-6 weeks. Therefore, at the beginning of treatment, the relevant hormone indicators are measured every 4-6 weeks, and then the dosage of Eugenol is adjusted according to the test results until the treatment goal is reached. After the treatment target is reached, the relevant hormone indexes need to be rechecked every 6-12 months. If the treatment does not reach the target, the reasons should be carefully searched, such as whether the patient is informed of the correct time and precautions to take the medication, and whether there are any conditions that affect the absorption of the medication, one by one.