What are the three major contraindications for taking vitamin B1?

Vitamin B1 is mainly available in tablets, injections, and other forms. Generally speaking, there is no established concept of "three contraindications for taking vitamin B1." The main contraindications for taking vitamin B1 include avoiding taking it on an empty stomach, avoiding alcohol consumption, avoiding concomitant use with medications such as aspirin, avoiding concomitant use with Chinese patent medicines containing tannins, and avoiding concomitant use with alkaline medications. It is recommended to consult a qualified physician before use. Detailed explanations are as follows:

1. Avoid taking on an empty stomach: Vitamin B1 is water-soluble. Taking it on an empty stomach may lead to rapid absorption into the bloodstream, but it may be excreted from the body via the kidneys before being fully utilized, resulting in reduced effectiveness. It is recommended to take vitamin B1 after meals or with meals to enhance its absorption.

2. Avoid alcohol consumption: Alcohol can damage the gastrointestinal mucosa and impair the transport function of the intestinal mucosa, thereby reducing the absorption and utilization of vitamin B1. Alcohol consumption should be avoided during the period of taking vitamin B1.

3. Avoid concomitant use with medications such as aspirin: Vitamin B1 may cause a decrease in gastric pH, while aspirin may be hydrolyzed into salicylic acid in the stomach. The combination of the two may irritate the gastric mucosa and potentially cause gastrointestinal disorders.

4. Avoid concomitant use with Chinese patent medicines containing tannins: Some Chinese patent medicines, such as Sijiqing tablets and Shuzhi pills, contain tannins that may combine with vitamin B1 to form precipitates, affecting the absorption and efficacy of vitamin B1.

5. Avoid concomitant use with alkaline medications: Vitamin B1 is easily degraded in an alkaline environment, thereby reducing its efficacy. It is generally not recommended to use it in combination with alkaline medications such as aminophylline.

Individuals with allergic constitutions or hypersensitivity to certain components of vitamin B1 should take it cautiously to avoid triggering allergic reactions. In addition, excessive intake of vitamin B1 may lead to side effects such as headache, fatigue, irritability, loss of appetite, diarrhea, and edema. It is recommended to strictly follow medical instructions when taking vitamin B1.