Top 100 Drugs: Which Are Your Patients Taking?

The eye doesn't exist in a vacuum. Knowing the most commonly used medications by indication can help you provide the best possible care.

Release Date:

September 2016

Expiration Date:

September 15, 2019

Goal Statement:

Medical intervention on many disease states currently relies on pharmolcogical modalities. This course provides an overview of the most prescribed branded drugs from 2014-2015. It includes summaries of their risks to the eye as well as the systemic risks. Mechanisms of action are described in brief, and the top 100 drugs are categorized in terms of their primary indications.

Faculty/Editorial Board: 

Len V. Koh, OD, PhD 

Credit Statement: 

COPE approval for 2 hours of CE credit is 51057-PH for this course. Check with your local state licensing board to see if this counts toward your CE requirement for relicensure.

Disclosure Statement: 

The author has no relationships to disclose.

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As primary eye care practitioners, our patient population covers the breadth of the human lifespan, and we are busy clinical bees applying our expertise to a wide range of conditions to provide care for our diverse cohort. 

Although we as optometrists prioritize vision, we also need to consider the whole health of our patients. The eyes are extensions of the brain, and the ocular system is an integral part of the body. But patients often view the eyes as isolated entities, which is made clear when they present to the office without their current prescriptions or a medication history in hand. In our modern holistic and systems-based approach to eye care, we are on alert for patients who take systemic medications with the potential to cause adverse reactions within the ocular system. To help preserve their vision, we need to first know what our patients are taking.       

The Top 100 

Although the FDA approves dozens of new drugs each year, it is rare for any particular new drug to become a blockbuster in the market in the first few years. Focusing on the top 100 prescribed medications ensures we cover the meds we are likely to see on a daily basis in the clinic. Table 2 lists the top 10 therapeutic classes by prescription.¹ Table 1 contains the top 100 drugs in the United States from April 2014 through March 2015, according to their ranking by research firm IMS Health.² This article highlights many of the more common drugs you may encounter in your practice and their potential impact on ocular health. Use it as a systemic Rx refresher and to stay informed of new developments and new and existing clinical key points. 

Note: This top 100 list contains only the most prescribed branded drugs, so it is by no means a comprehensive accounting of the drugs our patients are taking—generics and over-the-counter drugs, of course, are taken by many patients. Bear this distinction in mind for all discussions of volume/popularity in the ensuing article. Furthermore, the notable systemic and adverse reactions discussed in the article are excerpted from the packaging inserts for each respective drug, as submitted to the FDA and accessible via DailyMed.³

Possibly the most important point to remember within the context of the top 100 is that a number of drugs are known, potentially, to cause reversible or irreversible visual impairment.⁴ 

Click image to enlarge. Click here to download PDF version.

Diabetes medications. Treatments for diabetes account for the most prescriptions in the United States, with more than 64 million, including multiple forms of insulin, various classes of hypoglycemic drugs and medications to treat pain from nerve or muscle impairment. This is not surprising—it is estimated that 29.1 million Americans, or 9.3% of the population, suffered from diabetes in 2012.⁵ The number of new cases has been projected to grow each year by 1.4 million.⁵ 

A common medication taken by many of our diabetes patients is Lyrica (pregabalin, Pfizer), approved for epilepsy and the management of neuropathic pain associated with diabetic peripheral neuropathy, postherpetic neuralgia, fibromyalgia and neuropathic pain associated with spinal cord injury. Approximately 10 million prescriptions were written in the United States for Lyrica during the 2014-2015 period of the IMS study.² 

Adverse effects. Hypoglycemia is a primary concern for patients taking various forms of insulin and insulin secretagogues such as sulfonylureas. Early symptoms of hypoglycemia include pounding heart, racing pulse, pale skin, sweating, trembling, anxiety, dizziness and weakness. A few options to treat hypoglycemia in-office include glucose tablets, hard candies and a half-cup of fruit juice or soft drink. Each of these contains about 15 grams of fast-acting carbohydrate. Educate your patients with diabetes on the importance of medical nutrition therapy and regular annual eye exams.⁶ In controlled studies, blurred vision was reported in 7% of patients, and visual field changes were detected in 13% of patients treated with Lyrica.³

Opiate medications. Moderate and severe pain are commonly treated with µ-opioid full agonists such as Oxycontin (oxycodone, Purdue Pharma), which had more than 5.3 million prescriptions in the study year.²  

Adverse effects. Boxed warnings for Oxycontin include addiction, abuse and misuse, and life-threatening respiratory depression. Suboxone (Indivior)—a combination of buprenorphine, a µ-opioid receptor partial agonist and naloxone, a µ-opioid receptor antagonist—had nearly seven million prescriptions in the United States for the treatment of opioid dependence.¹ In some states, such as Ohio and Pennsylvania, first responders carry emergency opioid overdose kits and administer Narcan (naloxone hydrochloride, Adapt Pharma) to revive opioid addicts from an overdose.

Respiratory drugs. Collectively, these drugs, which primarily include β₂-adrenergic agonists (BA) and corticosteroids, comprised more than 56 million American prescriptions in 2014-2015.² β₂-adrenergic agonists can be short- or long-acting (LABA) and, like corticosteroids, are used to treat asthma. Muscarinic antagonists such as Spiriva (tiotropium, Boehringer Ingelheim) and Atrovent (ipratropium bromide HFA, Boehringer Ingelheim) are more effective at opening the airways than both corticosteroids and BA in patients with chronic obstructive pulmonary disease (COPD) and emphysema.³ 

Adverse effects. The potential ocular side effects of muscarinic antagonistic drugs are similar to cycloplegics, including mydriasis, blurred vision and angle closure. Because the potential ocular side effects of long-term corticosteroid use include increased intraocular pressure (IOP) and posterior subcapsular cataract, we should measure IOP and dilate patients with histories of respiratory disorders to thoroughly evaluate the lenses and optic nerves. LABAs have black-box warnings for the increased risk of asthma-related death. Thus, patients should be educated on the potential side effects of LABAs such as confusion, dizziness, arrhythmia, body pain, trembling and seizures—all of which require emergency attention. 

Hyperlipidemia medications. These include statins such as Crestor (rosuvastatin calcium, AstraZeneca) and cholesterol absorption inhibitors such as Zetia (ezetimibe, Merck). Often, drugs from these two classes are sold in combination. Welchol (colesevelam, Daiichi Sankyo), a bile acid sequestrant, is indicated for the treatment of both high cholesterol and Type 2 diabetes. Over 32 million prescriptions for statins alone or in combination were written to reduce blood cholesterol in the United States in the 2014-2015 period.¹ 

Adverse effects. Patients on statins need to be reminded of the risks for myopathy, including rhabdomyolysis, which manifests as muscle pain, tenderness or weakness. Zetia in combination with statins can elevate liver enzymes; thus, liver function tests should be performed at the initiation of therapy. Welchol may decrease the absorption of fat-soluble vitamins A, D, E and K, so patients should take vitamin supplements at least four hours prior to their normal dose. Since hyperlipidemia increases the risk for retinal arterial and vein occlusions, a comprehensive eye exam is recommended.

Antihypertensive drugs. Calcium channel blockers, angiotensin receptor antagonists and β-blockers, on the whole, have been the most prescribed drugs for the past five years, yielding close to 25 million US prescriptions in 2014-2015.² This number would be even higher if the rankings were to include the generic forms, as most of the thiazide diuretics, angiotensin converting enzyme (ACE) inhibitors and β-blockers are available as generic drugs. β-blockers are one of the most commonly prescribed drugs on the market because they are widely used for a variety of cardiovascular diseases, including hypertension, angina pectoris and heart failure. Of course, optometrists are familiar with its topical formulation, timolol, for the treatment of glaucoma. 

Adverse effects. It's important to pay close attention to this large group of patients by taking blood pressure and perfoming a retinal exam because of their risk for stroke or retinal vein occlusion secondary to hypertensive vascular changes such as arteriovenous nicking. 

Fetal toxicity is a boxed warning for angiotensin receptor antagonists such as Benicar (olmesartan medoxomil, Daiichi-Sankyo), so patients who are pregnant should not take the drug. Similarly, drugs that act directly on the renin-angiotensin system, such as the ACE inhibitor Zestril (lisinopril, AstraZeneca), can cause injury and death to the fetus.

Table 2. Top 10 Therapeutic Classes by Prescriptions1
Dispensed Prescriptions (Millions)		2010	2011	2012	2013	2014
1	Antihypertensives	652	649	691	701	705
2	Mental health	481	495	511	523	537
3	Pain	462	462	470	482	480
4	Antibacterials	271	274	272	269	267
5	Lipid regulators	255	255	266	264	263
6	Antidiabetes	173	174	186	193	201
7	Nervous system disorders	142	148	157	168	179
8	Anti-ulcerants	147	150	159	166	170
9	Respiratory	153	153	157	162	169
10	Thyroid therapies	110	113	122	127	130

The boxed warning for β-blocking agents indicates that these drugs must be tapered off over one to two weeks with careful monitoring to prevent exacerbations of angina pectoris and myocardial infarction. The most common adverse reactions with systemic β-blockers tend to be mild and transient, manifesting as tiredness, dizziness, depression and bradycardia. Furthermore, β-blockers may mask tachycardia, an early sympathetic symptom in hypoglycemic diabetes patients.

Thyroid medications. Synthroid (levothyroxine sodium tablets USP, AbbVie) was the most commonly prescribed branded drug in the 2014-2015 study year, with more than 21.5 million US prescriptions.² It is approved for hypothyroidism and pituitary thyroid stimulating hormone suppression. Hypothyroidism is a broad category consisting of primary (thyroidal), secondary (pituitary), tertiary (hypothalamic) and subclinical hypothyroidism. Primary hypothyroidism may result from functional deficiency, primary atrophy or from the effects of surgery, radiation or drugs, with or without presence of goiter. 

As practitioners, we must be alert for thyroid eye disease and diagnose it early in our patients. Exophthalmometry at an initial visit can serve as a baseline for future comparison. Patients can be educated on the early symptoms of thyroid eye disease such as dry eye, redness, light sensitivity, lid retraction and eye protrusion. Furthermore, thyroid eye disease occurs three times as often in females than in males, and it can arise even when a patient is euthyroid.⁷

Adverse effects. Thyroid hormones should not be used for weight loss or to treat obesity because overdose can be serious or life threatening, especially when taken together with sympathomimetic amines, which are used to suppress the appetite. 

Anti-ulcerants. These are the eighth most commonly prescribed drugs by indication.² Nexium (esomeprazole magnesium, AstraZeneca) and Dexilant (dexlansoprazole, Takeda Pharmaceuticals) account for over 19 million prescriptions in the United States.² Other commonly prescribed anti-ulcerant drugs such as ranitidine and omeprazole available in generic forms. Carafate (sucralfate, Aptalis Pharmaceutical Technologies), available in suspension, is also an anti-ulcerant with more than one million prescriptions.² It is only indicated for short-term treatment—up to eight weeks for an active duodenal ulcer.

Adverse effects. Chronic use of proton pump inhibitors for more than a year can increase the risk of osteoporosis-related fractures of the hip, wrist and spine.³ Furthermore, conjunctivitis and abnormal vision have been reported with incidence of less than 1%.³ Constipation was the most frequent complaint with Carafate use (2%).³ Diabetes patients are at risk of hyperglycemia when using this drug.³

Combination oral contraceptives (COC). An estrogen (estradiol) and a progestogen (progestin) are often combined to suppress ovulation and increase cervical mucus to inhibit sperm penetration. Over 15 million prescriptions for branded COCs, such as Lo Loestrin Fe (norethindrone acetate & ethinyl estradiol, Allergan) were written in the study year.²However, the number of patients taking COCs is significantly higher, considering the top 100 does not account for generic versions of these medications. 

Adverse effects. The boxed warning on COCs includes cigarette smoking and its ability to increase the risk for serious cardiovascular events such as stroke and myocardial infarction. Patients taking COCs should be aware of potential serious side effects that could be easily remembered by the mnemonic ‘ACHES’: Abdominal pain, Chest pain, Headaches (severe), Eye problems and Swelling of the legs and thighs. Dry eye and retinal vein thrombosis have been associated with COCs as well.³

Arthritis and osteoarthritis medications. Brand-name drugs for this indication were doled out to over 15 million Americans, not including the many generic versions available.² Celebrex (celecoxib, Pfizer) and Voltaren Gel (diclofenac sodium topical gel, Novartis) are the nonsteroidal anti-inflammatory drugs (NSAIDs) that make the top 100 branded list. Two branded drugs commonly used to treat arthritis are tissue necrosis factor alpha (TNF- α) inhibitors Enbrel (etanercept, Amgen) and Humira (adalimumab, AbbVie). 

Adverse effects. The boxed warning for Celebrex indicates that the drug increases the risk for myocardial infarction and stroke. Additionally, Celebrex is a sulfonamide that may cause serious adverse skin events such as Stevens-Johnson syndrome. All NSAIDs can cause serious gastrointestinal adverse events, including bleeding, ulceration and perforation of the stomach or intestines. 

A few other side effects of systemic NSAIDs worth knowing: they can worsen pre-existing hypertension, decrease renal blood flow and induce bronchospasm. Finally, keep in mind the risk of Reye’s syndrome, a very rare but serious disease affecting primarily the brain and liver with symptoms of drowsiness, confusion, seizures, coma and, in severe cases, death. These usually develop three to seven days after the viral illness starts. It most likely occurs in children younger than 15 years of age.⁸ The exact etiology is unknown, but it has been reported in patients who took aspirin and recently had chicken pox, a cold or flu.⁸ 

For TNF-α inhibitors, serious infections and malignancy are the boxed warnings because they are immune suppressants, exposing patients to opportunistic infections. Most patients who developed these infections were taking concomitant immune suppressants such as methotrexate or corticosteroids. Lymphoma and other malignancies have been reported in patients treated with TNF-α inhibitors.³ As for ocular side effects, optic neuritis and cataract are potential adverse effects. Furthermore, patients with arthritis also have increased risk of uveitis.

Psychiatric medications. Central nervous system (CNS) stimulants such as Vyvanse (lisdexamfetamine dimesylate, Shire) and Focalin XR (dexmethylphenidate hydrochloride, Novartis) are indicated for attention deficit hyperactivity disorder (ADHD), as is Strattera (atomoxetine, Eli Lilly).

Schizophrenia affects about 1% of Americans, with onset occurring mainly between the ages of 16 and 30.⁹ Atypical antipsychotics such as Abilify (aripiprazole, Otsuka America Pharmaceuticals), Seroquel XR (quetiapine fumarate, AstraZeneca) and Latuda (lurasidone, Sunovion Pharmaceuticals) are the drugs of choice for schizophrenia; however, they are also indicated, and may be prescribed for, other psychological concerns such as bipolar I disorder, major depressive disorder (MDD) and autistic disorder. 

MDD is characterized by having at least two weeks of a major depressive episode that causes significant distress and disability. It is not associated any history of mania or hypomania as in bipolar disorder. The annual community prevalence rate is about 7% in the United States, affecting three times more young patients—i.e., those 18 to 29 years old—than patients over 60 years of age.¹⁰ 

Pristiq (desvenlafaxine, Pfizer), a serotonin and norepinephrine reuptake inhibitor (SNRI), and Viibryd (vilazodone, Allergan), a 5HT1A partial agonist, are two branded drugs for MDD. Selective serotonin reuptake inhibitors (SSRIs) such as Prozac (fluoxetine, Eli Lilly), Paxil (paroxetine, GlaxoSmithKline), Zoloft (sertraline, Pfizer) are also indicated for treating MDD, along with many generic versions. 

The Top Five Drugs by Class  The top five therapeutic classes by prescription (both branded and generic) for the past five years in order of frequency are antihypertensives, mental health, pain, antibacterials and lipid regulators (Table 2 lists the top 10 drugs by class).1 This ranking correlates well with disease prevalence in the United States, and we should take this into consideration when treating patients. For instance, we should pay more attention to hypertension by taking blood pressure in-office and be on the lookout for early signs of hypertensive retinopathy. Additionally, we could do more for our patients by reviewing their medications and screening for early mental health issues via questionnaires available from Mental Health America.5

Adverse effects. CNS stimulants are amphetamine derivatives and have a high potential for abuse and dependence. They have been associated with weight loss and slowing of growth rate in pediatric patients; thus, close monitoring of growth (weight and height) in pediatric patients is recommended. Blurred vision, mydriasis and difficulties with visual accommodation have been reported as post-marketing experiences. Strattera, which is not a derivative of amphetamine, has a low potential for abuse but an increased risk of suicidal ideation in short-term studies in children or adolescents with ADHD. Families and caregivers are advised to monitor for unusual changes in behavior, especially during the initial few months of therapy.

The boxed warning for atypical antipsychotics indicates that elderly patients are at increased risk of death due to dementia-related psychosis and suicidal thoughts and behaviors. Antipsychotic drugs work by blocking dopamine receptors, and in rare cases, can cause tardive dyskinesia and neuroleptic malignant syndrome, a rare but potentially fatal condition manifesting as hyperpyrexia, muscle rigidity, altered mental status and autonomic instability (i.e., irregular blood pressure and heartbeat). 

The ocular side effects of typical or older antipsychotics such as phenothiazines (chlorpromazine and thioridazine) are widely known for their deposits in the retina, lens and cornea.¹¹ Although atypical or newer antipsychotics are less harmful to the eye, they have more metabolic side effects such as hyperglycemia, dyslipidemia and weight gain. 

The boxed warning for MDD drugs states that, according to studies of short-term use (i.e., few months) antidepressants increase the risk of suicidal thoughts and behavior in children, adolescents and young adults. When caring for patients of all ages who are taking antidepressants, be sure to monitor closely for adverse psychiatric effects. Advise families and caregivers of the need for close observation and communication with the prescriber.    

Alzheimer’s disease (AD). Therapies include Namenda (memantine HCl, Allergan), a glutamatergic receptor blocker, and Exelon (rivastigmine, Novartis), a cholinesterase inhibitor, with about 11 million prescriptions between 2014 and 2015.

Adverse effects. Various visual anomalies, including color vision, visual fields, stereopsis and contrast sensitivity, have been reported in patients with AD, but they are hard to replicate consistently.¹² It is likely that AD deteriorates visual function, and it may be difficult for patients to describe visual problems as dementia worsens, so we must pay attention to patients’ complaints and do the best we can to optimize their visual function and improve their quality of life. Caregivers can play an essential role in observing and recording any difficulty with vision-related tasks and report to the eye care provider.¹² Cholinesterase inhibitors (e.g., Exelon) enhance the cholinergic system and can induce miosis.

Erectile dysfunction medications. Viagra (sildenafil citrate, Pfizer) and Cialis (tadalafil, Eli Lilly) are phosphodiesterase-5 (PDE-5) inhibitors indicated for the treatment of erectile dysfunction (ED). Cialis is also approved for the treatment of benign prostatic hyperplasia. Thus, it is prudent that we do not assume all patients are taking these medications primarily for ED. 

Adverse effects. Patients need to be reminded that ED medications potentiate the hypotensive effect of nitrates, such as nitroglycerin for angina. Color vision disturbances have been associated with PDE-5 inhibitors because they have the ability to also block PDE-6 in the retina. Non-arteritic anterior ischemic optic neuropathy (NAION) has been reported as a possible result of PDE-5 inhibitors, but it could also be a coincidence, since elderly patients have increased risk of NAION.³Nevertheless, patients with prior history of NAION should be warned of increased risk of recurrence.

Benign prostatic hyperplasia (BHP). This occurs in almost all men as they age, and about half of all men over the age of 75 have some symptoms, so the number of patients taking Avodart (dutasteride, GlaxoSmithKline), a 5α-reductase inhibitor, may be significant. Vesicare (solifenacin succinate, Astellas Pharma), a muscarinic antagonist, and Myrbetriq (mirabegron, Astellas Pharma), a β₃-adrenergic agonist, are approved for the treatment of overactive bladder, with symptoms of a sudden, strong and uncontrollable urge to urinate. 

Adverse effects. Like other muscarinic antagonists, Vesicare can cause blurry vision, dry eye and angle closure. We are familiar with Flomax (tamsulosin, Boehringer Ingelheim), an 1-adrenoceptor blocker that has been associated with floppy iris syndrome, which can complicate cataract surgery.

Anticoagulants. Brand-name drugs indicated to prevent stroke accounted for nearly 11 million prescriptions in the IMS study.² They include factor Xa inhibitors such as Pradaxa (dabigatran, Boehringer Ingelheim) and thrombin inhibitors such as Eliquis (apixaban, Bristol-Myers Squibb) for reduction of risk of stroke and systemic embolism in nonvalvular atrial fibrillation, and platelet aggregation inhibitors such as Effient (prasugrel, Eli Lilly) for maintaining anticoagulation in the treatment of deep vein thrombosis and pulmonary embolism. 

Adverse effects. These drugs increase the risk for bleeding, so patients may need to avoid elective dental work or elective surgical procedures. Additionally, premature discontinuation of oral anticoagulants can increase the risk of thrombotic events. Some patients may present to your office with severe subconjunctival hemorrhage secondary to adverse effects. The International Normalized Ratio (INR) is typically 0.9 to about 1.1 for healthy individuals. On warfarin therapy, the INR elevates to between 2 and 3.5.¹³ But INR may not be accurate in assessing the effectiveness of newer anticoagulants such as Pradaxa or Xarelto (rivaroxaban, Janssen Pharmaceuticals); more effective tests tailored to these novel drugs are being developed.^13,14 

Glaucoma medications. These commonly prescribed drugs are near and dear to our specialty. More than 9.5 million brand-name prescriptions were given out in the study year to decrease IOP in glaucoma patients.² Lumigan (bimatoprost ophthalmic solution,Allergan), Travatan Z (travoprost ophthalmic solution, Alcon), Alphagan P (brimonidine tartrate ophthalmic solution, Allergan) and Combigan (brimonidine tartrate/timolol maleate ophthalmic solution, Allergan) are the top four branded drugs for glaucoma. 

Adverse effects. Brimonidine can cause allergic conjunctivitis and conjunctival hyperemia, whereas prostaglandin analogs such as bimatoprost can cause conjunctival hyperemia, itchy eyes, eyelash growth and skin hyperpigmentation. Another side effect of long-term prostaglandin analog use is prostaglandin-associated periorbitopathy, which results in very deep superior sulcus and a ‘sunken’ eye appearance.¹⁵

Various ophthalmic medications. Other ophthalmic drugs that make the top 100 ranking are Patanol (olopatadine, Alcon) and Pataday (olopatadine, Alcon), with over four million prescriptions in the United States for the treatment of ocular itching associated with allergic conjunctivitis in the study year.²

Durezol (difluprednate ophthalmic emulsion, Alcon), the newest topical steroid, and the corticosteroid Lotemax (loteprednol etabonate, Bausch + Lomb) garnered more than one million prescriptions each for the treatment of inflammation and pain associated with ocular surgery.² 

Adverse effects. Some of the most common side effects of olopatadine are cold-like symptoms and pharyngitis in about 10% of patients. Burning or stinging, conjunctivitis, hyperemia and keratitis are other potential ocular adverse effects. Patients should wait at least 10 minutes after instilling olopatadine before inserting contact lenses because the benzalkonium chloride preservative can be absorbed by soft lenses. 

As for steroids, we know they are contraindicated in active ocular infections such as herpes simplex keratitis, fungal keratitis and bacterial keratitis. Prolonged steroid use can lead to increases in IOP and the formation of posterior subcapsular cataract, although perhaps less so with Lotemax.

HIV antivirals. For patients who have access to therapy, HIV infection can be managed as a chronic disease.¹⁶ Although AIDS-related illnesses are decreasing, cardiovascular disease and cancer are increasing in HIV patients because of long-term immunodeficiency and the cumulative toxicities incurred from antivirals.¹⁶ Norvir (ritonavir, AbbVie) and two other combination antivirals, Truvada (emtricitabine/tenofovir disoproxil fumarate, Gilead) and Atripla (efavirenz/emtricitabine/tenofovir disoproxil fumarate, Bristol-Myers Squibb) are the commonly prescribed branded antivirals.

Practitioner and Patient Resources For practitioners: Dailymed (https://dailymed.nlm.nih.gov), a website run by the US National Library of Medicine, contains 80,188 drug listings as submitted to the FDA.3  For patients: Patient assistance program resources can help the public access assistance or discounts to costly drugs. These are run by nonprofit organizations such as Partnership for Prescription Assistance (www.pparx.org), NeedyMeds (www.needymeds.org), RxAssists (rxassist.org) and others. Moreover, many drug companies run their own patient assistance programs, so you can direct patients to the company’s web site and apply for the discounts.4

Adverse effects. The drug labels warn of lactic acidosis (low blood pH) and severe hepatomegaly with steatosis (fat liver). Optometrists should be alert for signs of severe liver problems manifested as yellow eyes. Furthermore, patients with HIV are at increased risk of eye infections, ocular malignancy and HIV retinopathy. 

Vaccines and antivirals. The herpes zoster vaccine Zostavax (Merck) was administered to more than 2.2 million Americans to prevent shingles in individuals 50 years of age and older in the study year.² It is a live vaccine and is not recommended for individuals who are immunosuppressed or immunodeficient. Optometrists should educate older patients about the vaccine because herpes zoster ophthalmicus can cause severe pain and threaten vision.

Over 12.6 million vaccines were given to prevent or treat influenza in the form of the influenza vaccines Afluria (BioCSL) and Tamiflu (oseltamivir phosphate, Genentech). During 31 seasons between the years 1976 and 2007, flu-associated deaths in the United States ranged from a low of about 3,000 to a high of about 49,000. People 65 years of age and older accounted for 80% to 90% of the flu-related deaths.¹⁷ 

Rounding Out the Top 100 

The above drug categories comprise the bulk of the top 100 branded medications cited by IMS Health.² Other notable drugs and their indications are as follows. All figures are taken from the IMS data and represent US-only prescribing patterns.²

Smoking cessation. Chantix (varenicline, Pfizer) made the list with over 2.2 million prescriptions.² It is a nicotinic receptor partial agonist that can lead to changes in behavior, hostility, agitation and suicide ideation. 

Chronic angina. Ranexa (ranolazine, Gilead), a sodium current inhibitor, is used to treat adults with chronic angina and can be used with other cardiovascular drugs. 

Irritable bowel syndrome (IBS). Linzess (linaclotide, Allergan), a guanylate cyclase agonist, treats IBS with constipation (IBS-C) and chronic idiopathic constipation (CIC). The most common side effect is diarrhea within the first two weeks of treatment. Amitiza (lubiprostone, Takeda Pharmaceuticals), for CIC, is a chloride channel activator. 

Gout. Uloric (febuxostat, Takeda Pharmaceuticals), a xanthine oxidase inhibitor, was prescribed more than 1.2 million times for the management of chronic hyperuricemia in patients with gout during the year studied.² It is contraindicated in patients prescribed azathioprine or mercaptopurine, as it increases the risk of cardiovascular thromboembolic events and hepatic failure. 

Acne. Epiduo (Galderma Laboratories) is a combination of adapalene (a retinoic acid nuclear receptor agonist) and benzoyl peroxide (an oxidizing agent with bactericidal effect) and is the most prescribed branded topical acne agent in the world.¹⁸ Eyelid edema, contact dermatitis and conjunctivitis have been identified in post-marketing experience. 

Migraine. Relpax (eletriptan HBr, Pfizer), a 5HT1B/1D receptor agonist, is indicated for the acute treatment of migraine. Since it is a serotonin agonist, serotonin syndrome may occur, particularly during co-administration with selective SSRIs and other antidepressants. Serotonin syndrome symptoms include agitation, hallucinations, coma, irregular heartbeat and blood pressure and hyperthermia. 

By highlighting these drugs, we gain essential knowledge pertinent to us as primary care optometrists. Additionally, though the rankings in Table 1 would be different if generic drugs were included, the general principles of care described in this article are relevant to generic drugs in corresponding classes. 

Dr. Koh is an associate professor at Arizona College of Optometry, Glendale, AZ. 

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