Flumazenil
What is flumazenil?
Flumazenil can be thought of as a Valium blocker. It was first used in the late 1980s and has since traded under a variety of names, including Mazicon, Romazicon and Flumazepil. Flumazenil reverses the effects of benzodiazepines.
Flumazenil’s primary use with patients has been to reverse the affects of sedation used in surgery or other medical procedures and to treat benzodiazepine overdose. It is usually administered as a single injection, with the dose and frequency being based on the patient’s response.
Flumazenil is currently registered for use in Australia and is one of the main drugs used in Australia for benzodiazepine overdose.
Subcutaneous flumazenil
Fresh Start Recovery Programme is currently using flumazenil to help with the withdrawal of patients from a range of benzodiazepines.
Flumazenil can prevent the brain feeling the effects of benzodiazepines. This means that for someone receiving a flumazenil infusion there will be little, if any, effect when taking benzodiazepines. It does not affect any other drugs that might be used, only drugs within the benzodiazepine family.
By using the flumazenil at a low dose and over a short period the GABA-A receptors in the brain are thought to be reset, and the drug lessens the urge to take benzodiazepines. Additionally research at Fresh Start has demonstrated that it lessens the withdrawal symptoms and helps lower the feeling of anxiety and physical symptoms associated with withdrawal. After they have finished the infusion the receptors will be much more sensitive and the patient will be able to feel their body’s own natural benzodiazepines again.
The dose of flumazenil is very low and is administered through a small, 26 gauge needle which is placed just under the skin in the abdominal area. The flumazenil is mixed with a small amount of saline and placed into a portable infusion device. The device delivers the flumazenil in a continuous flow.
The O’Neil Springfusor, used for flumazenil infusion.
The amount that is given is set at the time of infusion and is monitored twice daily. The treatment requires several days placement in Fresh Start’ Medical House where the patient can be supervised. The site of infusion is examined as well as the level of withdrawal and overall health. The infusion usually lasts for a 96 hour period, but can be extended where required.
Caroline was put on Stilnox (zolpidem) by her doctor but found that she needed to keep increasing the dose. “I tried to stop it but the doctor didn’t want to take me off it,” says Caroline. She found herself using more than 20 tablets every day. “I would use one every time I got shaky so that no-one would know I was addicted,” says Caroline. Then she came to Fresh Start and had flumazenil infusions to detoxify from the sedative. “Things are so much better now – there are no cravings or anything that would make me want to go back to that lifestyle.”
Adverse reactions to flumazenil
As the administration of the infusion is through a subcutaneous route there is a low risk of infection in the site, which would show up as redness, swelling or a discharge. There is also a slight risk of the development of haematomas (bruising) surrounding the site. Adverse reactions due to the flumazenil could include headaches, sensitivity to light for the duration of the infusion, slight nausea, body fatigue, sweating, a dry mouth and dizziness.
In a minority of the patients undergoing treatment with flumazenil there is a risk of seizures and/or convulsions. Due to the risks associated with flumazenil, the treatment requires several days of supervised accommodation.