Top 20 generic molecules worldwide:

Top 20 generic molecules worldwide:

The big news in generic drugs in the last couple of years has been all of the marquee brands that are getting their tails kicked by generic competition. The best example is the loss of the patent on Lipitor, Pfizer's ($PFE) cholesterol-lowering drug, which was the best-selling pharmaceutical ever.

Still, worldwide, the picture of generics is somewhat different. There are plenty of places in the world without insurance to pay for big-name treatments, even in generic forms at hugely reduced prices. So what are the best-selling generics around the world? Using 2011 data on generic molecules from researcher IMS Health, we give you the top 20 best-selling generic molecules globally. We list them along with the top three products for that molecule, and their makers in most cases, along with sales and percentage sales growth or loss info.

Generic Lipitor is on the list of course. In fact, the molecule in Lipitor, atorvastatin, recorded an 83.5% sales growth, although percentage-wise that was half the jump for the molecule used in generics of Sanofi's ($SNY) anticoagulant Lovenox. Some of the meds on the list are not prescription drugs but everyday over-the-counter products that are safe, effective, cheap, easy to make, easy to transport, and easy to store and so likely to show up everywhere in the world.

It is probably no surprise that a pain reliever tops the list, but would you have expected that a contraceptive would come in second? There are also a number of blood pressure medications, an antibiotic, and two proton pump inhibitors, but only one medication for treating diabetes.

Paracetamol  :
Top 3 products: Efferalgan; hydrocodone/acetaminophen, Watson Pharmaceuticals ($WPI); Tylenol
2011 sales: $6.12 billion
Sales change: 4.4%

Paracetamol, or acetaminophen, is a commonly used pain reliever and fever reducer. It has lots of product names around the world but is probably best known in the U.S. as Tylenol. Some consumers in the U.S. were outraged when Tylenol became hard to get after maker Johnson & Johnson ($JNJ) recalled the product due to a "musty smell" and then had to close the over-the-counter plant where most of its product was made because it was a mess.

Ethinyl estradiol:
Top 3 products: Loestrin 24 Fe, Zarah, Diane
2011 sales: $3.05 billion
Sales change: 22.3%

I am not sure what it says that this ingredient in oral birth control pills falls second on the global list behind a headache remedy.

Omeprazole:
Top 3 products: Omeprazole, Mylan ($MYL); omeprazole, Novartis ($NVS); omeprazole, Teva Pharmaceutical Industries ($TEVA)
2011 sales: $2.59 billion
Sales change: -4.5%

This proton pump inhibitor treats stomach upset issues like peptic ulcers or gastroesophageal reflux disease. Think Prilosec in the U.S. 

Amoxicillin :
Top 3 products: Amoxicillin, Novartis; amoxicillin/clavulanate; amoxicillin, Teva
2011 sales: $2.41 billion
Sales change: 4.1%

The antibiotic is used worldwide to treat bacterial infections including ear infections and gonorrhea. It is made by lots of generic drugmakers throughout the world.

Ibuprofen:
Top 3 products: Nurofen, Advil, Dolormin
2011 sales: $1.98 billion
Sales change: 9%

Whether it is known as Midol, Motrin, Cap-Profen or Advil, the pain reliever is used to ease the discomfort of everything from menstrual cramps to pain from arthritis.

Amlodipine:
Top 3 products: Amlodipine/benazepril, Teva; amlodipine/benazepril, Novartis; amlodipine/benazepril, Lupin Pharmaceuticals
2011 sales: $1.9 billion
Sales change: 0.4%

Pfizer ($PFE) controlled the sales of this blood pressure med, which it manufactured as Norvasc, for years.

Atorvastatin:
Top 3 products: Atorvastatin, Watson; atorvastatin, Ranbaxy Laboratories; atorvastatin, Apotex
2011 sales: $1.79 billion
Sales change: 83.5%

Look for this generic of Pfizer's ($PFE) king of all drugs, Lipitor, to top this list next year. In the first 6 months of this year, worldwide sales of generic Lipitor had already hit $1.7 billion, IMS Health reports.

Acetylsalicylic acid:
Top 3 products: Aspirin, Bayer; Kardegic; aspirin vitamin C, Bayer
2011 sales: $1.66 billion
Sales change: 6.4%

Even after being around for more than 100 years, aspirin continues to be one of the best-selling generics in the world. It was first isolated in 1897 by Bayer chemist Felix Hoffmann.

Simvastatin:
Top 3 products: Simvastatin, Teva; simvastatin, Novartis; simvastatin, Mylan
2011 sales: $1.64 billion
Sales change: -0.5%

Two years ago, before Lipitor went generic, this generic version of cholesterol reducer Zocor from Merck ($MRK) held the No. 7 spot currently occupied by atorvastatin. That two cholesterol-lowering molecules are in the top 10 globally says something about the health of the world.   

Clavulanic acid :
Top 3 products: Amoxicillin/clavulanic acid, Novartis; amoxicillin/clavulanic acid, Teva; Augmentin
2011 sales: $1.63 billion
Sales change: 8.4%

This is the yang to the yin of amoxicillin, which lands at No. 4 on this list. Clavulanic acid is combined with the penicillin group of antibiotics to fight some forms of  antibiotic resistance. It is generally reserved for bacterial infections caused by strains that are resistant to amoxicillin.

Fentanyl:
Top 3 products: Fentanyl, Mylan; fentanyl, Watson; fentanyl, Teva
2011 sales: $1.61 billion
Sales change: 1.3%

Fentanyl is used for breakthrough pain for conditions like cancer. But with its strength comes some issues with this opioid. About 5 years ago, Cephalon had to warn doctors to use it very carefully after at least three patients died and others experienced severe side effects because of improper dosing or substitutions, or because they should never have been given opioids in the first place.

Diclofenac:
Top 3 products: Voltaren; Torsilax; diclofenac, Sanofi ($SNY)
2011 sales: $1.61 billion
Sales change: 15.5%

Diclofenac is a nonsteroidal anti-inflammatory drug (NSAID). It is often used globally to treat chronic pain associated with cancer as well as for conditions like arthritis or osteoarthritis. In fact, Covidien ($COV) uses it in a topical solution for osteoarthritis to reduce stomach upset.

Metformin:
Top 3 products: Metformin, Teva; Glucophage; Metformin, Mylan
2011 sales: $1.57 billion
Sales change: 3.2%

Given the pace at which people throughout the world are being diagnosed with and treated for diabetes, it is a little surprising that a molecule associated with a diabetes drug doesn't rank higher on this list. This oral drug is the go-to treatment worldwide for type 2 diabetes.

Venlafaxine:
Top 3 products: Venlafaxine, Teva; venlafaxine, Upstate Pharma; venlafaxine, UCB
2011 sales: $1.57 billion
Sales change: -2.6%

The generics of this antidepressant have been available for about 6 years now but not yet for the extended-release version of Pfizer's drug Effexor XR. A number of retail pharmacy chains last year sued Pfizer ($PFE) and Teva, alleging that they colluded to delay generic versions of the extended-release version, a claim the two companies, of course, deny.

Salbutamol:
Top 3 products: Salamol; salbutamol, Mylan; albuterol, Nephron Pharmaceuticals
2011 sales: $1.57 billion
Sales change: 9%

Salamol, or salbutamol, has been around for more than 40 years and is the go-to inhaler product for people suffering from asthma. It is still sold under brand names such as Ventolin by GlaxoSmithKline ($GSK) but is also sold by a host of generics makers.

Pantoprazole:
Top 3 products: Pantoprazole, Teva; pantoprazole, Novartis;  Pantozol
2011 sales: $1.56 billion
Sales change: -7.1%

Like the molecule omeprazole, which is third on this list, pantoprazole is a proton pump inhibitor used to treat conditions like gastroesophageal reflux disease.    

Hydrochlorothiazide:
Top 3 products: Losartan/HCTZ, Lupin; Lozap H; Delix Plus
2011 sales: $1.55 billion
Sales change: 3.6%

This diuretic, often abbreviated HCTZ, is used for treatment of kidney disease and also shows up in any number of blood pressure medicines. Its detection in Russian cyclist Alexandr Kolobnev during the 2011 Tour de France was enough for him to bow out, although it was later determined that he had taken it for legitimate medical reasons.

Enoxaparin sodium:
Top 3 products: Enoxaparin, Novartis; enoxaparin, Sanofi; Versa
2011 sales: $1.53 billion
Sales change: 198%

The generics are copycats of the Sanofi anticoagulant Lovenox and came into the market in a big way two years ago, somewhat ahead of what Sanofi had expected.

Metoprolol:
Top 3 products: Metoprolol, Par Pharma; metoprolol, Watson;
metoprolol, Wockhardt America
2011 sales: $1.53 billion
Sales change: -1.7%

This beta blocker is one that shows up around the world under a whole host of brand names and as generics. Used primarily to treat high blood pressure, it is prescribed for some other heart conditions and occasionally for mild anxiety or migraines.

Dexamfetamine:
Top 3 products: Amphetamine/dexamfetamine, Teva; amphetamine/dexamfetamine, Watson; amphetamine/dexamfetamine, CorePharma
2011 sales: $1.4 billion
Sales change: 17.3%

This is the molecule that is used in drugs for attention-deficit hyperactivity disorder (ADHD) and is most commonly associated with Adderall XR from Shire ($SHPG). Shire supplies the two authorized generics found here to Teva and Global Pharmaceuticals, the generics division of Impax Laboratories ($IPXL). In June, Actavis, now owned by Watson, brought the first third-party rival to the market.