May 20, 2022

What is Red Man Syndrome? When antibiotics are given too quickly

The increase in antibiotic-resistant bacteria has led to increased use of the antibiotic vancomycin, which has been shown to be effective in treating nasty infections like MRSA. However, it can also trigger an uncomfortable reaction known as red man syndrome.

Characterized by an itchy red rash on the face, neck and upper torso, the condition is rarely serious – although severe cases can involve symptoms such as low blood pressure, tachycardia (rapid heartbeat) and chest pain.

Also known as vancomycin flushing syndrome (VFS), red man syndrome is an anaphylactoid reaction caused by the rapid infusion of vancomycin. This happens when the drug triggers the release of histamine from mast cells and basophils – two components of the immune system. This differs from an anaphylactic reaction in that it is not mediated by immunoglobulin antibodies.

Vancomycin was originally obtained from the jungle soil in Borneo in the 1950s, and early treatments tended to have a brown coloration due to the presence of impurities. This earned the drug the nickname “Mississippi slime”. While VFS was originally blamed on these contaminants, this theory was dismissed when the condition occurred even when the drug was purified.

Typically used as a first-line drug for several types of antibiotic-resistant bacterial infections, as well as postoperative wound infections and some bloodstream infections, vancomycin does not always trigger VF, although the reaction often occurs if the drug is administered too quickly. An infusion rate of one gram of vancomycin per hour has been associated with red man syndromecurrent guidelines therefore recommend that the drug be administered at approximately ten milligrams per minute.

In most cases, symptoms of VFS begin to appear between four and ten minutes after starting the first dose of vancomycin, although in rare cases the syndrome may appear up to a week after treatment. Red man syndrome is usually more prevalent in people under 40, with children being the most susceptible.

Fortunately, the syndrome is easily managed with common antihistamines, and symptoms tend to resolve in about 20 minutes. Red man syndrome is not thought to cause lasting damage, and it is good to continue treatment with vancomycin after all signs of VFS have disappeared.

It appears that the reaction can be avoided by ensuring that the drug is given slowly. However, some patients may require pretreatment with antihistamines if they have shown particular sensitivity to VFS.

Despite its scary name, red man syndrome is actually not that serious and usually resolves itself fairly quickly after treatment. That said, a small number of serious and life-threatening cases have been reported, so doctors are now advised to administer vancomycin slowly and carefully.