Can I administer an intravenous (IV) push of thiamine 100 milligrams (mg)?

From the Guidelines

Yes, you can administer thiamine 100 mg as an IV push, as recommended by the most recent guidelines 1. Thiamine (vitamin B1) can be given as a slow IV push at a rate of 100 mg over 5 minutes (approximately 20 mg/minute). When administering, dilute the medication in a small volume of normal saline or D5W if not already in solution form. Monitor the patient during administration for adverse reactions, particularly hypotension or anaphylaxis, which are rare but possible. Thiamine administration is particularly important in patients with suspected Wernicke's encephalopathy, alcoholism, malnutrition, or before giving glucose to patients at risk for thiamine deficiency. The IV route provides rapid delivery of thiamine to the central nervous system, which is crucial in emergency situations where deficiency can lead to irreversible neurological damage. Some key points to consider:

• The ESPEN micronutrient guideline recommends thiamine administration in patients at risk for deficiency, with a suggested dose of 100 mg, 3 times a day, IV 1.
• The guideline also emphasizes the importance of thiamine administration in patients with suspected Wernicke's encephalopathy or other conditions that may lead to thiamine deficiency 1.
• Other studies support the use of thiamine in patients undergoing bariatric surgery or with other conditions that may lead to thiamine deficiency 1. After the IV push, follow your institution's protocol for documentation of medication administration.

From the FDA Drug Label

In the treatment of Wernicke-Korsakoff syndrome, thiamine hydrochloride has been administered IV in an initial dose of 100 mg, followed by IM doses of 50 to 100 mg daily until the patient is consuming a regular, balanced diet. Patients with marginal thiamine status to whom dextrose is being administered should receive 100 mg thiamine hydrochloride in each of the first few liters of IV fluid to avoid precipitating heart failure.

Administration of IV Push of Thiamine 100mg:

• The FDA drug label supports the administration of thiamine 100mg via the IV route, but it does not explicitly state that it can be given as an IV push.
• However, it does mention that thiamine hydrochloride has been administered IV in an initial dose of 100 mg in the treatment of Wernicke-Korsakoff syndrome 2.
• It is also recommended to administer 100 mg thiamine hydrochloride in each of the first few liters of IV fluid to avoid precipitating heart failure in patients with marginal thiamine status to whom dextrose is being administered 2.
• Key Consideration: The label warns that thiamine must be administered slowly by the IV route in the treatment of “Wet” beriberi with myocardial failure, but this does not directly apply to the administration of a 100mg dose for other indications 2.
• Clinical Decision: Given the information provided, it appears that thiamine 100mg can be administered IV, but the label does not provide clear guidance on the administration rate, and other sources should be consulted to determine if an IV push is appropriate.

From the Research

Administration of Thiamine via IV Push

• The question of whether an IV push of thiamine 100mg can be administered is addressed in several studies 3, 4, 5.
• According to a study published in 2017, patients at high risk of Wernicke's encephalopathy should immediately receive an intravenous or intramuscular dose of thiamine 3.
• Another study from 2018 discusses the use of high-dose intravenous thiamine in patients with encephalopathy, but does not specifically address the administration of 100mg via IV push 4.
• A 2017 study published in The Canadian journal of hospital pharmacy describes thiamine prescribing practices for adult patients admitted to an internal medicine service, where low-dose therapy was defined as 100 mg IV daily 5.
• However, there is no direct evidence in the provided studies that specifically addresses the safety and efficacy of administering an IV push of thiamine 100mg.
• A study from 2022 evaluated the safety of 500 mg intravenous push thiamine and found no anaphylactic reactions and a low rate of injection site reactions 6, but this dose is higher than the 100mg in question.

Safety and Efficacy

• The safety of thiamine administration via IV push is discussed in several studies, with rare cases of anaphylactic shock and injection site reactions reported 3, 6.
• However, the study from 2022 found that administration of IV push 500 mg thiamine was not associated with anaphylactic events and was associated with a low rate of injection site reactions 6.
• The efficacy of thiamine administration via IV push for specific conditions, such as Wernicke's encephalopathy, is discussed in several studies 3, 4, 5.

Dosage and Administration

• The optimal dosing of thiamine for various conditions, including Wernicke's encephalopathy, is not well established and varies across studies 3, 4, 5.
• The study from 2017 published in The Canadian journal of hospital pharmacy found that low-dose thiamine (100 mg IV daily) was prescribed for 81.6% of patients, while high-dose thiamine was prescribed for 18.4% of patients 5.