Crestor

Crestor (Rosuvastatin) – 22.27m

At 22.27 million, Crestor was the most prescribed drug in the US in 2014. The cholesterol-lowering drug, developed by British pharmaceutical company AstraZeneca , received FDA approval on August 12th 2003 and was launched in the US market soon after.

Rosuvastatin lowers the levels of bad cholesterol (LDL) and triglycerides in the blood, while increasing good cholesterol (HDL). Crestor, which belongs to a group of drugs called statins, also slows down plaque build-up in arteries.

Synthroid (Levothyroxine) – 22.25m

Prescriptions for the hypothyroid treating drug Synthroid, developed by American pharmaceutical company Abbott Laboratories , totalled 22.25m over the observed period. Despite being present in the US market since 1955, Synthroid was only approved on 24 July 2002 as it predated FDA rules and regulations.

Synthroid is a synthetic hormone identical to thyroxine and treats hypothyroidism. It is prescribed when the body’s thyroid gland does not produce sufficient thyroxine hormone by itself and is usually taken for life.

Nexium

Nexium (Esomeprazole) – 17.76m

Nexium, a proton pump inhibitor developed by AstraZeneca that decreases the amount of acid produced in the stomach gained 17.76m prescriptions in the US. Nexium was launched in March 2001 following FDA-approval in the preceding month.

The drug is used for the treatment of gastroesophageal reflux disease (GERD), erosive esophagitis and pathological hypersecretory conditions such as Zollinger-Ellison Syndrome. It is also used to prevent gastric ulcers associated with the use of nonsteroidal anti-inflammatory drugs (NSAIDs) or those caused by Helicobacter pylori.

Ventolin HFA (Albuterol) – 17.74m

Ventolin HFA, an albuterol inhaler for asthma that is developed by UK-based multinational pharmaceutical company GlaxoSmithKline recorded 17.74m prescriptions in the US. The quick-relief inhaler gained FDA-approval on 19 April 2001 and was subsequently launched in the US in February 2002.

Ventolin HFA treats or prevents bronchospasm in asthma patients by opening the airways of the lungs to ease breathing. The bronchodilator provides respiratory relief for four to six hours.

Advair Diskus

Advair Diskus (Fluticasone propionate/salmeterol) – 14.49m

Advair Diskus, an asthma inhaler manufactured by GlaxoSmithKline, totalled 14.49 prescriptions in the US. The inhaler was launched in the US market in April 2001 following FDA approval in August 2000.

Advair Diskus is used to treat chronic obstructive pulmonary diseases (COPD) including chronic bronchitis and emphysema. It is a combination of two drugs: fluticasone, an anti-inflammatory medicine, and salmeterol, a long-acting bronchodilator. The drugs help improve lung function by preventing airway constriction and inflammation.

Lantus SoloSTAR (Insulin glargine injection) – 10.45m

Doctors in the US prescribed 10.45 million Lantus SoloSTAR disposable insulin pens to patients with diabetes mellitus between October 2013 and September 2014. Lantus SoloSTAR is developed by Sanofi-Aventis and was approved by the FDA on 25 April 2007. The drug was launched in the US in July 2007.

The pen is pre-filled with Lantus or insulin glargine, a long-acting human insulin analogue, which is administered subcutaneously. The drug lowers the amount of glucose in blood and is used for the treatment of hyperglycaemia in patients with type 1 or type 2 diabetes.

Vyvanse

Vyvanse (lisdexamfetamine dimesylate) – 10.14m

Vyvanse, a central nervous system stimulant, totalled 10.14 prescriptions in the US. The drug gained FDA approval on 23 February 2007 and was launched in the US in July 2007. The prescription medicine was originally developed by New River Pharmaceuticals . Biopharmaceutical company Shire gained control of the drug for commercialisation and future development when it acquired New River in February 2007.

The drug is used in the treatment of attention deficit hyperactivity disorder (ADHD) and controls systems of the disorder such as inattention, hyperactivity, impulsivity and impairment in social, academic or occupational functioning.

Lyrica (Pregabalin) – 9.79m

Anti-epileptic drug Lyrica, developed by American pharmaceutical corporation Pfizer, totalled 9.79m prescriptions. The anticonvulsant drug was launched the US market in September 2005 following FDA-approval on 30 December 2004.

Lyrica is indicated for the treatment of diabetic peripheral neuropathy, post herpetic neuralgia and fibromyalgia. It is effective in the treatment of neuropathic pain associated with spinal cord injury and partial onset seizures in adults.

Spiriva Handihaler

Spiriva Handihaler (Tiotropium bromide) – 9.55m

At 9.55m, Spiriva Handihaler, an anticholinergic medicine manufactured by German pharmaceutical company Boehringer Ingelheim Pharmaceuticals , is one of the most prescribed drugs in the US. The drug gained FDA approval on 30 January 2004 and was launched soon after.

A dry powder formulation of the bronchodilator tiotropium is contained in the Spiriva capsule and is inhaled orally using the HandiHaler inhalation device. The drug enlarges the airways to facilitate breathing and controls symptoms associated with COPD.

Diovan (Valsartan) – 9.47m

Diovan, one of the top-selling anti-hypertensive medications in the world, totalled 9.47m prescriptions in the US alone. The drug was developed by Novartis , approved by the FDA on 23 December 1996 and launched in the US in March 1997.

Diovan is an angiotensin receptor blocker and is used in the treatment of high blood pressure (hypertension) and heart failure. It reduces the risk of cardiovascular mortality in heart attack patients. The drug works by relaxing and widening blood vessels improving blood flow.