L-T4 should be taken after sufficient time interval for certain special medications or foods: 1. 1 hour interval with vitamins and tonic; 2. 2 hours interval with iron and calcium containing foods or medications; 3. 4 hours interval with milk and soy foods; The best way is to get up early in the morning on an empty stomach and stick to it daily. If you forget to take your medication in the morning, replenish it as soon as you remember. If you can’t remember all day, take twice as much the next day. If you forget for many days, even a week, it seems safer to take them all at once than to drop them completely. If you take the medication on a full stomach, the food can slightly interfere with the absorption of T4. Therefore, it is best to take a period of time between taking the medication and using breakfast (the instructions for Eugenol recommend at least 30 minutes for this reason), and to avoid soy preparations because they can interfere with the absorption of T4 in the intestine. Remember to always take it on time and in the right amount to keep the TSH at the desired level.