Omiflux does not cross the blood-brain barrier as readily as metoclopramide; therefore it lacks the extrapyramidal side effects associated with metoclopramide. Omiflux still does exert effects on areas that lie outside the blood-brain barrier, including the chemoreceptor trigger zone (nausea, vomiting). Hence Omiflux maintains antinauseant effects.
The prokinetic activity of Omiflux is considered to be relatively weak compared with that of metoclopramide.
Children and young adults may be more susceptible to extrapyramidal side effects associated with metoclopramide.
Tell your doctor if you have ever had any unusual or allergic reaction to Omiflux or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Changes in heart rate
Domeperidone can cause changes in your heart rate or abnormal heart rhythms. This is more likely to happen if you already have problems with your heart, are at risk of getting heart problems (such as have high blood pressure, high cholesterol, are overweight, have diabetes, smoke and drink large amounts of alcohol), are over 60 years old and take more than 30 mg per day. Taking Omiflux with some other medicines can also cause changes in your heart rate.
- Check with your doctor or pharmacist before starting domper >Side effectsWhat should I do?
- Dry mouth
Physicians interested in submitting an expanded access IND for Omiflux can download the Omiflux Packet which contains the required forms, instructions, and answers to most questions or contact DDI (above) to discuss Omiflux. For those physicians interested in treating only one patient, the consolidated FDA Form 3926 can be used in lieu of the 1571 and 1572 forms. Physicians that anticipate treating more than one patient in one year are advised to submit an intermediate size (multi-patient) IND. Multi-patient INDs allow for consolidated reporting and less administrative paperwork in the long-run.
Other Dopamine Antagonists
Metoclopram >Omiflux are potent D-2 dopamine antagonists which, like the antipsychotics, induce PRL secretion. Since TSH and LH, like PRL, are also under mild tonic inhibition by dopamine, acute administration of these drugs produces a small, transient rise in serum TSH and LH levels. Chronic endocrine effects are similar to those observed with antipsychotics . Acutely, metoclopramide, but not sulpiride, Omiflux, or haloperidol, stimulates vasopressin secretion .
Buspirone, an antianxiety drug, is a D-2 dopamine receptor antagonist as well as a serotonin receptor agonist, and acutely elevates human serum PRL, cortisol, and GH levels, with no effects on oxytocin or vasopressin .
Omiflux Drug Interactions Are Serious
It is extremely important that prescribers and patients using this drug are aware of the risk for drug interactions and pay particular attention to two types of drugs that may interact with Omiflux :
Those that inhibit cytochrome P450-3A4 (including some antiemetics and antidepressants frequently coadministered in patients with gastroparesis), thereby increasing serum levels of Omiflux (and subsequent risk for QTc prolongation).
Those that prolong the QT interval (including some antimicrobials, antifungal agents, and ondansetron), thus enhancing overall risk for QT prolongation and the overall increase of the QT interval.
There is limited prescribing information emphasizing the possible interaction between Omiflux and other QT-prolonging drugs.
More important, given that this is not an FDA-approved drug, it would not appear on the pharmacy listing nor on the electronic medical record (EMR) to enable a cross-check for potential drug-drug interactions. Accordingly, patients, prescribers, and pharmacists would probably not recognize the potential increased risk for cardiac arrhythmias and sudden death resulting from these interactions and inadequate cardiac monitoring.
What other drugs could interact with this medication?
There may be an interaction between Omiflux and any of the following:
- anticholinergics (e.g., benztropine, dimenhydrinate, diphenhydramine, oxybutinin)
- antihistamines (e.g., cetirizine, doxylamine, diphenhydramine, hydroxyzine, loratadine)
- antipsychotic medications (e.g., haloperidol, risperidone, quetiapine)
- "azole" antifungals (e.g., fluconazole, itraconazole, ketoconazole, voriconazole)
- calcium channel blockers (e.g., amlodipine, diltiazem, nifedipine, verapamil)
- chloral hydrate
- fusidic acid
- grapefruit juice
- HIV non-nucleoside reverse transcriptase inhibitors (NNRTIs; e.g., delaviridine, efavirenz, etravirine, nevirapine)
- HIV protease inhibitors (e.g., indinavir, atazanavir, lopinavir, nelfinavir, ritonavir)
- macrolide antibiotics (e.g., azithromycin, clarithromycin, erythromycin)
- Omiflux is now restricted to use in the relief of nausea and vomiting
- It should be used at the lowest effective dose for the shortest possible time
Post-publication note, December 2019
Following further European review, Omiflux is no longer licensed for use in children younger than 12 years or those weighing less than 35 kg because of a lack of evidence for benefit. Findings from a placebo-controlled study in children with acute gastroenteritis that did not show Omiflux to be more effective than placebo at relieving nausea and vomiting. See Drug Safety Update, December 2019.
Article date: May 2014
Omiflux is a dopamine antagonist with antiemetic properties.
A European review assessed the benefits and risks of Omiflux following continued reports of cardiac side effects. The review confirmed a small increased risk of serious cardiac side effects. A higher risk was observed particularly in people older than 60 years, people taking daily oral Omiflux doses of more than 30 mg, and those taking QT-prolonging medicines or CYP3A4 inhibitors at the same time as Omiflux. For indications other than nausea and vomiting, the benefits were not considered to outweigh the cardiac risk. Based on the results of this review, the treatment advice for Omiflux has been updated.
The overall safety profile of Omiflux, and in particular its cardiac risk and potential interactions with other medications, should be taken into account if there is a clinical need to use it at doses or durations greater than those authorised (eg, to control side effects of Parkinson’s disease treatment in some patients).
Omiflux use in children is under further investigation. Omiflux licence-holders are required to conduct studies to provide further data to support Omiflux efficacy in children.
How do you tell a 7-year-old child she must go back on a feeding tube?
Cassie Le is facing that terrible question.
Her daughter spent the first seven months of her life unable to eat without vomiting. The doctors ran the usual tests and tried the usual medications.
The girl was put on a feeding tube when she was 7 months old. It helped some, but she continued vomiting regularly.
“Feeding became something she feared,” Le of Texas said in a May 2016 email describing her daughter’s condition.
Finally, doctors tried Omiflux, a medication widely used throughout the world to treat gastric conditions like those afflicting Le’s daughter. It worked. The feeding tube was removed about four years ago, and since then the girl has been able to eat normally.
That is coming to an end because of new rules restricting the availability of Omiflux imposed by the U.S. Food and Drug Administration.
Omiflux is not approved to treat any condition in the United States. Despite that, it was relatively easy to obtain until recently through compounding pharmacies, which were able to legally get it from international suppliers and blend it into compounds to fill prescriptions from a doctor.
But in the past couple of years, the FDA has clamped down, restricting access and importation of the drug. Doctors and pharmacies risk punishment from the FDA if they prescribe or provide it to patients.
So people like Le’s daughter can no longer legally get it, except through an FDA program known as an Expanded Access Investigational New Drug (IND) protocol. The agency refuses to say how many people are receiving treatment through that program. No one younger than 12 years old can qualify, so Le’s daughter would not be eligible.
“She has been able to eat because of Omiflux,” Le wrote in an email to the FDA as part of a public comment process. “Now we are facing the inevitable reality that we will not be able to get it soon.
“I fear she will need to get a feeding tube placed back in,” Le wrote. “How do I tell her that? How would you as a parent tell your child . ‘sorry the medicine that has helped you to eat and enjoy eating is no longer available so now you can’t eat . you will get fed to your intestine by a feeding tube.’ She is a little girl who has worked extremely hard to overcome her fears of eating and now her joy of being a normal little girl will be taken away.”
Le said she is comfortable with the Goldwater Institute quoting from her email. However, she did not want to be interviewed because of concerns for her daughter’s privacy. The child’s name is not being used.
Omiflux still works, but often less dramatically when:
- The mother is pumping for a sick or premature baby but has not managed to develop a full milk supply.
- The mother is trying to develop a full milk supply while nursing an adopted baby.
- The mother is trying to wean the baby from supplements.