Tamiflu Vs. Relenza

What is difference between Tamiflu and Relenza? Tamiflu and Relenza which is better? How to decide between Tamiflu and Relenza? How to treat influenza? How to treat flu? What are side effects of Tamiflu and Relenza?
Health & Beauty > Pharmacy & Drugs

Both Tamiflu (Oseltamivir) and Relenza (Zanamivir) are antiviral medicines used primarily in the prevention and cure of influenza, commonly referred to as the flu. If given during the first 48 hours, they can reduce the duration of the illness by a day or two and accelerate recovery.

During the last decade they have become particularly important, both medically and commercially, amidst the threats of an influenza pandemic.  As the only anti-viral drugs reasonably effective for influenza, they are being vigorously studied by researchers, while their manufacturers compete with each other to gain a larger share of commercial sales and profits. Recently, Glaxo Smith Kline, the manufacturer of Relenza,  launched a 3 year clinical study that will compare the efficacy of intravenous Zanamivir (Relenza) with oral Oseltamivir (Tamiflu) in treating hospitalized patients of influenza across 20 countries.

Tamiflu

Tamiflu is the trade name under which the Oseltamivir compound is marketed by its manufacturer, Hoffmanne-la-Roche. Tamiflu was developed by three researchers, C.U. Kim, W. Lew, and X. Chen of Gilead Sciences, a US based concern, which licensed it to Roche. Since 1999, it has been the most commonly prescribed drug for influenza, and its demand has skyrocketed. 

Relenza

Relenza is the trade name under which the Zanamivir compound is marketed by its manufacturer, Glaxo Smith Kline. Relenza was developed in 1989 by a team of scientists, led by Mark von Itzstein at the Monash University, in a research funded by an Australian biochemical company, Biota, which licensed the patent rights to Glaxo in 1990, which began marketing it in 1999.

Tamiflu and Relenza : A comparison

Tamiflu and Relenza can be compared across several parameters like clinical efficacy, mode of action, drug formulation, side effects, viral resistance, stockpiling of the drug and commercial issues.

Mode of action & Clinical efficacy

Both Tamiflu and Relenza have a similar action by which they bring relief to a patient of influenza. They are both Neuraminidase inhibitors. They combine with the Neuraminidase enzyme of the influenza virus, thereby preventing it from replicating and spreading further throughout the body. Their clinical efficacy is also very similar. In patients of seasonal influenza, they accelerate the recovery by one or two days if given within the first 48 hours, and reduce the severity and complications. Given the fact that there are epidemics of seasonal influenza every year, Tamiflu and Relenza are the only effective antiviral drugs available, and in addition to vaccination shots, the only treatment available in our fight against influenza.

Drug Formulation

Tamiflu is marketed as oral tablets of 75mg, 45mg and 30 mg strengths as well as in the form of a syrup, making it easier for a patient to take. On the contrary, Relenza is marketed as powder that has to be inhaled, requiring an inhaler. The more convenient formulation of Tamiflu is considered one of the main reasons why the demand and sales of Tamiflu have usually exceeded Relenza till recently.

Major Side Effects

During the early trials and immediately after being marketed, Relenza was observed to worsen asthma and other obstructive lung diseases, sometimes even leading to Bronchospasm, a side effect not associated with Tamiflu. This led to Public Health Advisory warnings by the U.S. Food and Drug Administration (FDA) regarding use of Relenza in patients with respiratory diseases. Along with the inconvenience associated with inhaling Relenza, this was probably the other factor, which led to its lessening popularity among physicians. As a result,  Tamiflu was generally considered the drug of choice for seasonal flu until recently, in spite of the fact that both had similar actions and were equally effective in treating influenza.

Both Tamiflu and Relenza are generally well tolerated with less than 1% cases reporting side effects like nausea, vomiting, abdominal pain, diarrhea, headache, rash and allergic reactions. More toxic side effects have been rare with both drugs though hepatitis, seizure, confusion, aggravation of diabetes, and hemorrhagic colitis are reported in rare cases.

Since 2007, Japan, which is the single largest consumer of Tamiflu, has reported many cases of abnormal behaviour, hallucinations and disturbed consciousness associated with use of Tamiflu, leading to a warning by Japanese Health Ministry that Tamiflu should be avoided in the age group of 10 to 19 years, wherein the maximum such cases were observed. Since then, abnormal behavior has also been considered as one of the possible side effects of both Tamiflu and Relenza.

Drug Resistance

Influenza virus is a constantly mutating virus. Because of its high frequency of mutations, leading to change of its structure, it escapes immunity that humans develop against the virus. Recently, it has also been reported to have developed resistance to anti-viral drugs. So far, cases of viral resistance have been reported only against Tamiflu, whereas no viral resistance has been observed against Relenza, a finding that can have very significant implications in favor of Relenza in the long run.

Reports of viral resistance against Tamiflu have been surfacing sporadically since 2005, when Lancet published an article in its August 13 issue reporting resistance in 18% patients taking Tamiflu and none in the case of Relenza. More Recently, both the Center for Disease Control and Prevention (CDC) and the World Health Organization (WHO) have acknowledged in their reports that there is widespread resistance to Tamiflu in treating the H1N1 virus, the strain that caused the 2009 flu pandemic, with almost 99.6 % samples being resistant, against only 12% resistance an year earlier. The high incidence of viral resistance in the case of Tamiflu will make it less useful for treating influenza, a fact that can tilt the priorities in favor of Relenza, which has so far been free of the viral resistance problem.

Protective Stockpiling and Commercial Issues

The market demand for Tamiflu and Relenza has often skyrocketed in face of threats of influenza epidemics, and led to higher profits for their manufacturers. During the earlier years, preference for Tamiflu largely overshadowed Relenza. In 2000, Tamiflu outsold Relenza three times. In the first half of 2006, Roche sold Tamiflu worth $770 million, whereas Glaxo Smith Kline’s sales of Relenza were not even one-tenth of this amount. However, subsequently, with rising awareness among Governments about the possible threat of influenza pandemic, and their strategic stockpiling of these drugs, the demand for both the drugs has grown by leaps and bounds. In recent times, there have been some reports suggesting that sales of Relenza have at times even surpassed those of Tamiflu. However, Tamiflu still remains the preferred drug for fighting influenza in most parts of world. Since many countries are likely to continue with their strategic stock-piling, the demand for both drugs will continue to be healthy in immediate future, though the frenzy of 2009 may not be seen unless we face another influenza pandemic scare.

Overall Comparison

Tamiflu and Relenza are the only pharmaceutical remedies against influenza. In most cases, seasonal influenza or the common flu is self limiting. Both Tamiflu and Relenza, only accelerate the recovery by a day or so, leading to suggestions that it may be better to use them more selectively in very sick patients. Due to the more convenient oral tablet form of Tamiflu and the worsening of respiratory symptoms by Relenza inhalation, Tamiflu has generally been preferred over Relenza. Recent reports of abnormal behavior associated with Tamiflu and the higher degree of viral resistance against it has again tilted the scale somewhat in favor of Relenza. However, the current global demand of both antiviral drugs, arising primarily from protective stock piling of medicines against influenza pandemic, is high enough to absorb the production of both Tamiflu and Relenza in the near future.

7 comments

Add a comment

0 answers +0 votes
Post comment Cancel
deepblue
0
5 answers Posted on May 2, 2011
This comment has 0 votes  by
John Smither
0
17 answers Posted on Apr 21, 2011
This comment has 0 votes  by
V Kumar
0
2 answers Posted on Apr 6, 2011
This comment has 0 votes  by
Brian MacLennan
1
0 answers Posted on Apr 5, 2011
This comment has 0 votes  by
carol roach
0
46 answers Posted on Mar 30, 2011
This comment has 0 votes  by
V Kumar
0
2 answers Posted on Mar 30, 2011
This comment has 0 votes  by
Aunty Ann
0
548 answers Posted on Mar 29, 2011
This comment has 0 votes  by

Related articles

Quadriderm Cream

Quadriderm cream Quadriderm cream or ointment contains betamethasone as 17 - valerate (0.05%), gentamicin sulfate (0.1%), Tolnaftate (1%) and clioquinol (1%). Quadriderm cream or ointment - Tubes with 20 grams. What is Quadriderm cream used for? Quadriderm ointment or cream is a topical dermatol...

Chinese BL: Antifungal Cream

In the Philippines Chinese BL cream is categorized as a counterfeit drug – not that it is fake or ineffective, but simply it is an imported drug unregistered in the country’s Food and Drug Authority. Naturally, these products are banned in drugstores and other drug outlets. However, a Ch...

Disflatyl Uses and Side Effects

Disflatyl tablets uses and side effects Active ingredients- Simethicone. Disflatyl tablets amass the gas bubble formed in the stomach and intestine, helping easier routing of gas. It is prescribed for relief from pressure created by excessive formation of gas bubbles in the stomach and intestine. ...

LS BL: Antifungal Corticosteroid Cream

In the Philippines, LS BL cream is imported and distributed by Manxing Enterprise Corporation from Shanghai Baolong Pharmaceutical Co. Ltd in China. LS BL cream is legal as it is registered in the Food and Drug Authority (FDA).  Unfortunately, like the unregistered Chinese BL, there are also co...

Ascof and Solmux: A Comparison of Two Cough Remedies

In the Philippines, most cough remedies are considered as OTC or Over-The- Counter medications. Customers usually choose a product based on  drug popularity. The more they see or hear about it from the media, the more they feel secure in purchasing the product for their loved ones or for themse...

Tuseran Forte Uses and Side Effects

Tuseran Forte Active ingredients present in Tuseran Forte- dextromethorphan HBr, phenylephrine HCl and paracetamol. Dextromethorphan HBr, an anti-tussive, restrains the region in the brain that stimulates coughing. Phenylephrine HCl, a decongestant, loosens and clears airway passage allowing easie...

Surfaz SN Anti Fungal, Antibacterial and Anti-inflammatory Cream

Surfaz SN Anti fungal, Antibacterial and Anti-inflammatory cream Active ingredients • Clotrimazole I P 1.0% w/w • BeclomethasoneD propionate IP 0.025% w/w • Neomycin Sulphate I. P. 0.5% w/w • Cream base. q.s. • Preservatives. • Mettiyi Paraben I. P. 0.15% w...

Zentel Worm Medicine Dosage and Side Effects

Zentel worm Medicine dosage and Side effects Zentel active ingredients- Albendazole from the family of benzimidazole grouping of anthelmintic agents. Albendazole is a white to off-white, neutral or approximately fragrance-free fine particles, which is virtually insoluble in H20 and somewhat so...

Ectrin (Erdosteine)

Ectrin (Erdosteine) Active ingredient- Erdosteine Ectrin indications/ uses Ectrin (Erdosteine) is indicated for treating severe bronchitis, constant bronchitis as well as its exacerbations. It may as well be used for treating respiratory problems portrayed by uncharacteristic bronchial discharge ...

Grilinctus (Dextromethorphan Hydrobromide), Anti-allergic Cough Medicine

Grilinctus (Dextromethorphan Hydrobromide) Grilinctus (Dextromethorphan Hydrobromide) is a pleasant tasting composition of proved therapeutic agents. It provides symptomatic relief from dry, irritating and allergic cough. Grilinctus (Dextromethorphan Hydrobromide) is a combination; and provides a p...

Diprogenta Cream (Betamethasone Dipropionate)

Diprogenta Cream (Betamethasone dipropionate) Betamethasone is an artificial corticosteroid that is applied on the skin (topically). Betamethasone impersonates the effect of hydrocortisone (cortisol), the steroid generated naturally in the human system by the adrenal glands. Corticosteroids conta...

Taxim-O 200mg (Cefixime)

Taxim-O 200mg (cefixime) Cefixime(Taxim-O) is an 3rd generation oral cephalosporin antibiotic. It is administered to take care of tonsilitis, gonorrhea, as well as pharyngitis. The normal dosage is 400 mg in 2 separate doses for a period of about one week. Pharmacodynamics Pharmacokinetics Cefix...

Domstal Dosage and Side Effects

Domstal Dosage and side effects Domstal active ingredients- Domperidone and Cinnarizine . Domstal Used for • Treating motion sickness (nausea and/ or vomiting), • Treating feeling of feeling heavy after meal, • Treat heartburn, stomach discomfort and acidity, because of food ing...

Heraclene (Dibencozide) Capsule

Heraclene (Dibencozide) Capsule Active ingredients- Dibencozide Mechanism of action Heraclene (Dibencozide) Capsule amplifies the protein "effectiveness coefficient" for example, the proportion of "bound nitrogen" for protein fabrication in the system evaluated to "consumed nitrogen" with foo...

Enzomac (Typsin, Bromelain & Rutoside Trihydrate) Tablets

Enzomac (Typsin, Bromelain & Rutoside Trihydrate) Tablets Active ingredients Trpsin BP 48 Mg Bromelain 90 Mg Rutoside Trihydrate BP 100 Mg Total proteolytic activity not less than 1095 FIP units per tablet. (Papain method). Description- Enzomac contains a combination of two proteolytic enz...

Amydramine Syrup

Amydramine syrup Active ingredients- Na citrate, Diphenhydramine HCl and Menthol. Composition/5 mL - Na citrate 28.5 mg, Diphenhydramine HCl 7 mg and menthol 0.55 mg General information Amydramine syrup is a combination of Na citrate, Diphenhydramine HCl and Menthol and is from the group of am...

Tuseran Forte: More Facts, Contraindications and Warnings

Whenever a customer asks for a cold and cough drug for an adult, Tuseran Forte is the first choice by most pharmacies. Aside from its convenient form as a capsule, Tuseran Forte contains phenylephrine – a decongestant; dextromethorphan – a cough suppressant; and paracetamol – an an...

Celestamine Tablets

Celestamine tablets Active ingredients- Betamethasone and dexchlorpheniramine maleate. Celestamine belongs to the steroid family and works by inhibiting the production of compound in the body causing pain and inflammation. Celestamine is administered for treating many health conditions which inc...

Kremil S Side Effects (Simethicone)

Kremil S side effects (Simethicone) Kremil S is from the antacids family with antiflatulents. Kremil S binds the gas bubbles formed in the stomach together allowing easier passage of gas. They are administered for easing painful pressure due to excessive gas formation in the stomach and intestine. ...

Saridon (Paracetamol) Side Effects

Saridon Side effects Active ingredients – Paracetamol Saridon is administered for quick relief from pain and reducing fever associated to common cold and flu. Saridon (Paracetamol) is used to relief many conditions which includes migraine pain, headache, muscle ache, arthritis pain, backache...

Medicol Advance: Ibuprofen Softgel Capsule

Medicol is a popular brand name of ibuprofen, a NSAID or non-steroidal anti-inflammatory drug in the Philippines. It is similar with Midol, another notorious brand for ibuprofen. But, while Midol is known by most women as relief for PMS or pre-menstrual syndrome, Medicol has been popular for fever, ...

Calamine Lotion for Chickenpox

Chickenpox is a contagious disease caused by the varicella zoster virus.  It can spread through the air and by direct contact. Chickenpox develops ten to twenty days after contact with an infected person. While its symptoms include fever and malaise, the itchy rash that turns into blisters is t...

Myonal (Eperisone) 50mg

Myonal (Eperisone) 50mg Myonal active ingredients- Eperisone HCl Besides Myonal tablets also has carmellose, carnauba wax, microcrystalline cellulose, stearic acid, titanium oxide, calcium stearate, talc, sucrose, macrogol 6000, precipitated calcium carbonate, white shellac, cornstarch, hydroxy...

Chinese Fluocinonide Ointment: Facts and Warnings

Fluocinonide is a recognized topical medication for various skin disorders usually applied 2 to 3 times a day.  It is categorized as a corticosteroid useful for dermatitis, psoriasis, eczema and for other allergic skin inflammation.  Although, popular as an ointment, fluocinonide can also ...

Salicylic Acid for Ringworm

Salicylic acid is something to be associated to acetylsalicylic acid (ASA) also known as aspirin since it is a component of this medication. While a small amount of salicylic acid can be employed as a food preservative, it is commonly used as a topical medication for skin disorders like psoriasis, w...

Lagaflex (Carisoprodol)

Lagaflex (carisoprodol) Lagaflex (carisoprodol) belongs to the group of muscle relaxing drug that functions by thwarting pain feelings involving the nerves as well as the brain. Carisoprodol is administered along with rest and objective treatment to take care of injuries and supplementary excrucia...

Silverex Cream (Silver Sulfadiazine)

Silverex Cream (silver sulfadiazine) General information Silverex Cream (silver sulfadiazine) is from the family of topical sulfonamides applied for treating a wide range of dermatological diseases. Silverex Cream uses Silverex cream is used for treating as well as preventing infectivity in acu...

Enervon C Multivitamin Supplement

Enervon C Multivitamin Supplement Enervon C multivitamins are an amalgamation of a variety of vitamins and minerals that are regularly found in our daily food and other normal sources. Multivitamin are prescribed for treating deficiency of vitamins caused by illness like pregnancy, unhealthy nutri...

Sangobion Capsule

Sangobion capsule Active ingredients- 250 mg of Fe gluconate, 7.5 mcg of vitamin B12, 50 mg of vitamin C, 1 mg of folic acid, 25 mg of sorbitol, 200 mcg of  copper sulfate, 200 mcg of manganese sulfate. Sangobion indications/ uses Sangobion capsules are prescribed or administered for treati...

Dorflex

Dorflex composition - Dorflex Dorflex tablets Each tablet contains: Orphenadrine citrate 35 mg, Dipyrone 300 mg, Caffeine 50 mg Dorflex solution Each ml contains: Orphenadrine citrate 35 mg, Dipyrone 300 mg, Caffeine 50 mg Patient information - Dorflex Store in a cool place and pr...

Is Loratadine Really Non-Drowsy?

Antihistamines or anti-allergy drugs are regarded as the first-line of relief for symptoms of hay fever and skin allergies. There are two types of antihistamine drugs- the first generation and the second generation. While the old, FGA or first generation antihistamines (chlorphenamine, diphenhydrami...

Secnidazole Side Effects

Secnidazole side effects The most common side effects of imidazole derivatives are digestive problems like nausea, stomach pain, abnormal taste (metallic), glossitis and stomatitis. Have rarely been reported: skin rashes, mild leukopenia (reversible after discontinuation of treatment), dizziness, p...

Althrocin 250 Mg/ 500 Mg (Erythromycin)

Althrocin 250 Mg/ 500 Mg (Erythromycin) Althrocin (Erythromycin) belongs to a group of macrolide antibiotic that has an antimicrobial range comparable to or to some degree larger than that of penicillin, and is frequently administered for patients allergic to penicillin. For respiratory tract conta...

Nasathera Capsules

Nasathera capsules Active ingredients- Phenylpropanolamine and  Paracetamol.   Per capsule-phenylpropanolamine 25 mg and Paracetamol 325 mg.  Per 5 mL syrup- Paracetamol 240 mg and Phenylpropanolamine HCl 12.5 mg Nasathera is from the family of systemic sympathomimetic preparatio...

Fucicort Topical Cream

Fucicort Topical Cream Active ingredients: Fusidic Acid 2 % and betamethasone valerate 0.1 % Fucicort Topical cream belongs to the group of potent (group III) corticosteroids, along with antibiotics. Fusidic acid works as the active anti-bacterial component of Fucicort Cream which performs its an...

Conzace Multivitamins

Conzace Multivitamins Different vitamins found in our natural food are combined together to form multivitamins. When the regular meal fails to provide the required nutrients to the body multivitamin supplements are prescribed. In short Multivitamins are medicines use for treatment of vitamin defici...

Antamin (Chlorphenamine Maleate)

Antamin (Chlorphenamine maleate) Active ingredients- Chlorphenamine maleate General information Antamin (Chlorphenamine maleate) belongs to the group of alternate alkylamines administered as general antihistamines. Antamin uses The drug assists to alleviate signs of cold as well as allergy, lik...

Fluimucil (Acetylcysteine)

Fluimucil (Acetylcysteine) Active ingredients- Acetylcysteine Fluimucil (Acetylcysteine) is from the group of mucolytics administered for treating wet cough. Fluimucil (Acetylcysteine) uses/ indications It may be indicated for treating severe and chronic respiratory tract infection with plenty o...

Alvedon (Paracetamol) 500mg Tablet

Alvedon (Paracetamol) 500mg tablet Active ingredients- paracetamol Despite being used for over 100 years, research haven’t yet being able to understand the working of paracetamol, however it is presumed that Alvedon (Paracetamol) 500mg works by decreasing the secretion of prostaglandins in t...

Appetite Stimulant Facts

While some people perform strenuous exercises or take diet pills to lose weight, there are also individuals who would want to gain extra pounds. Athletes for instance, would want more muscles and to do that they must take a lot of protein enriched foods. Parents would want their kids to eat more to ...

Levocloperastine Fendizoate- a Better, More Effective Antitussive Agent

A lot of antitussive agents today act centrally and causes central adverse events such as sedation, vomiting, and nausea. Because of this, there has been a search for a peripherally-acting antitussive agent expected to not produce these central adverse effects. However, the peripherally-acting antit...

Ambroxol (Mucosolvan) Side Effects

Ambroxol (mucosolvan) side effects Ambroxol Hydrochloride is an effective expectorant administered for various respiratory problems. It is a medically proven active mucolytic agent. Ambroxol is used for treating respiratory tract infections and other lung infections, which includes inflammatory pul...

Methycobal Tablets (Mecobalamin 500 Mcg)

Methycobal Tablets (Mecobalamin 500 mcg) Each Methycobal sugar coated Tablet contains: Mecobalamin 500 mcg (Appropriate overages added) Color: Titanium Dioxide Methycobal is a mecobalamin drug, a co-enzyme of Vitamin B that transpires in the blood and the cerebrospinal fluid. It is utilized by the...

Biogesic (Paracetamol) Side Effects

Biogesic (paracetamol) Side effects Paracetamol is the generic name for Biogesic and use for treating moderate to severe pain, headache, fever, arthritis pain, and muscle ache. Biogesic tablets, though, does not alleviate the hardness, reddishness and inflammation linked to rheumatoid arthritis, bu...

Combiflam Tablets

Combiflam Tablets Active ingredients- Paracetamol and Ibuprofen Pharmacokinetics Ibuprofen is a powerful anti-inflammatory with painkilling and antipyretic activity. Its antipyretic and analgesic actions are additionally reinstated by paracetamol. Combiflam Adverse Reactions Combiflam Side Eff...

Sorbiline (Sorbitol Solution)

SORBILINE (SORBITOL SOLUTION) Each 10 ml of SORBILINE contains : TR1CHOL1NE CITRATE 0.55 g SORBITOL SOLUTION (70%) I.P. 7.15 g (Non-crystallizing) Excipients q.s. Color : Sunset Yellow FCF (Colour Index 15985) PRESENTATION ...

Elica Cream (Mometasone Furoate Cream)

Elica cream (mometasone furoate cream) Elica (mometasone furoate) Cream, 0.1%, is made up of mometasone furoate, USP for dermatologic use. Mometasone furoate is a artificial corticosteroid with anti- seditious action. Each gram of Elica Cream, 0.1%, comprises: 1 mg mometasone furoate, USP in a c...

Comparing Wal-Mart Pharmacy to Walgreens Pharmacy

There are a lot of options available when you need to fill a prescription.  Grocery store chains, superstore chains and traditional drug stores are on practically every block, ready, willing and able to supply you with your medicinal needs and good advice. Comparing superstore and traditional ...

Grilinctus BM TABLETS AND SYRUP

Grilinctus-BM In various disorders such as acute and chronic bronchitis and other bronchospastic disorders such as eosinophilia, there is a spasm of the bronchial muscles and irritation of the bronchial mucous membrane, leading to breathlessness and cough. In the symptomatic management of these di...

Erythromycin Antibiotic Alternatives

Erythromycin is a drug of choice in a case when a patient is allergic to penicillin. However, using the same antibiotic may result to tolerance. Here are other antibiotic alternatives that are often prescribed by physician in replacement for Erythromycin. Josamycin Josamycin has been marke...