The anti-viral drug Tamiflu is being changed. The amount of drug in each dose is being reduced from 12 mg to 6 mg to avoid medication errors. The more potent Tamiflu would sometimes become frothy when shaken, which made accurate measurements for dosages difficult. The labeling of the product will be changed to reflect this.
The 12 mg concentration will still be for sale at pharmacies until the product is sold out but it will not be marketed after that.
What is Tamiflu?
Tamiflu is a drug intended to prevent or treat influenza, which is given as an oral suspension or in capsule form. However, according to literature on the subject, if it is given after you already have the flu, it only lessens the duration of it by one day, rather than preventing it: "In a pooled analysis of all influenza-positive adults and adolescents enrolled into treatment studies, oseltamivir 75 mg twice daily for 5 days reduced the median duration of influenza illness by approximately one day from 5.2 days in the placebo group to 4.2 days."
In children aged one year to 12 years, Tamiflu reduced the number of days ill with flu by 1.5 days.
However, this was only for laboratory confirmed cases of flu and it did not reduce flu-like symptoms.
A study in asthmatic children showed that the medication did not work for this group of individuals.
Manufacturers say that Tamiflu may prevent flu if given within the first 48 hours of symptoms. There were 27 cases of laboratory confirmed flu out of 136 people not having treatment compared with 10 people out of 135 in the group taking Tamiflu. The state of health of the people in these groups was not mentioned.
Side-Effects of Tamiflu
Side-effects associated with Tamiflu are greater than in those who were given a placebo, but the placebo was not disclosed so depending on what it was may have impacted the study results. Very common side effects noted after Tamiflu are headache and nausea. Other common side effects are bronchitis, insomnia, vertigo, cough, rhinorrhoea, vomiting, abdominal pain, diarrhea, dyspepsia, lymphadenopathy, pneumonia, ear infections, sinusitis, dizziness, fatigue, nasal congestion, conjunctivitis and pain. The majority of the common side effects of Tamiflu are similar to the symptoms of flu.
Those who have asthma may have their condition aggravated or there may be the onset of asthma in previously healthy people.
Other less common side effects (occurring in less than 1 percent of cases), are dermatitis, rash, urticaria, eczema, convulsions and hallucinations.
Psychiatric effects were seen most often in children and teenagers taking the drug. The data sheet said: "In patients with influenza who were receiving Tamiflu, there have been postmarketing reports of convulsions and delirium (including symptoms such as altered level of consciousness, confusion, abnormal behavior, delusions, hallucinations, agitation, anxiety, nightmares), in a very few cases resulting in self-injury or fatal outcomes. These events were reported primarily among pediatric and adolescent patients and often had an abrupt onset and rapid resolution."
Japan banned the use of Tamiflu in young people aged between 10 and 19 years after 54 people died while taking the drug. The Japanese government said that 15 young people aged between 10 and 19 have jumped from buildings and a sixteenth person ran into traffic. Five of them have died after 2004. There were also seven reports of abnormal behavior in adults, including two who committed suicide.
Japanese doctors theorized that possibly Tamiflu was penetrating the blood/brain barrier because people with flu often have inflammation and this allows easier access of substances into the brain and could possibly cause a person to become disinhibited.
Other countries have chosen to add a warning to the drug, rather than ban it in that age group.
Contraindications:
People should not take the drug if they are allergic to any of Tamiflu’s ingredients (oseltamivir phosphate, sorbitol (E420), sodium dilhydrogen citrate (E331a), xanthan gum (E415), sodium benzoate (E211), saccharin sodium (E954), titanium dioxide (E171), tutti frutti flavoring including maltodextrins, propylene glycol, Arabic gum (E414) and natural banana, pineapple and peach flavor).
Those with fructose intolerance should not take Tamiflu.
People who should take special care are:
• Those who are ill enough to require hospitalization
• The immune-compromised
• People with chronic respiratory disease or chronic heart disease
• Children who have been born prematurely (less than 37 weeks gestation)
• Those with renal impairment
• Infants less than one year of age.
These groups have either not been studied or not enough is known about the safety and efficacy of Tamiflu for them.
Sources:
Roche Pharmaceuticals Data Sheet for Tamiflu - http://www.medicines.org.uk/EMC/medicine/10701/SPC/Tamiflu+12+mg+ml+powder+for+oral+suspension/#PRODUCTINFO
Tamiflu (oseltamivir phosphate) for Oral Suspension: Label Change-New Concentration (6 mg/mL), FDA Medwatch, page accessed 13th July 2011 - http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm262432.htm
New Scientist, 23rd March 2007 - http://www.newscientist.com/article/dn11451-japan-bans-tamiflu-for-teenagers.html
Tamiflu-related Strange Behavior and Sudden Death - http://www.npojip.org/english/no61.html
Reviewed July 14, 2011
by Michele Blacksberg R.N.
Edited by Alison Stanton
Joanna is a freelance health writer for The Mother magazine and Suite 101 with a column on infertility, http://infertility.suite101.com/. She is author of the book, 'Breast Milk: A Natural Immunisation,' and co-author of an educational resource on disabled parenting, in addition to running a charity for people damaged by vaccines or medical mistakes.