OTC Product Review

BY STEPHANIE SINDEN, B.Sc.Phm.

We’ve all seen the ads featuring Wayne Gretzky talking about his experience with osteoarthritis(OA). They’re part of McNeil Consumer Healthcare’s campaign to raise awareness of the risk factors and early symptoms of OA, which Gretzky and 2.7 million Canadians have in common.

Part of this campaign is the introduction of Tylenol Arthritis Pain Caplets, the only acetaminophen product in Canada to offer extended relief–up to eight hours–from OA pain. Each caplet contains 650 mg of acetaminophen in a patented bi-layer formulation. The first 325 mg layer dissolves quickly for fast action while the second 325 mg layer is time-released for long-lasting pain relief. Taking two Tylenol Arthritis Pain Caplets (2×650 mg) is equivalent to taking two doses of two Tylenol Regular Strength Caplets, four hours apart.

This new formulation combines the clinical benefits of immediate release Tylenol with the convenience of a reduced dosing frequency. The dosage for adults is two caplets every eight hours, as required. It is hazardous to exceed six caplets per day. Acetaminophen is indicated to provide temporary relief of the pain of arthritis, muscle aches and sprains, menstrual cramps, headaches, and aches and pains due to flu. This extended relief product would be appropriate whenever a longer duration of action (up to eight hours) is beneficial.

There is one major difference in dosing between regular Tylenol and the arthritis formula: Tylenol Arthritis Pain Caplets should be taken on an empty stomach, whereas immediate release Tylenol products may be administered with or without food. You also need to tell your patients to swallow the caplets whole, with water. If you take one of these caplets and place it in a glass of water, you can see how quickly one half of the product dissolves. You can also see the importance of water.

Patients should be informed that different types of arthritis require different treatment approaches. Osteoarthritis occurs when the cartilage in joints wears down, leaving bone to rub against bone. This can cause debilitating pain in some people. Since this pain is primarily non-inflammatory in nature, OA is best treated with range of motion and low-impact exercises to slow joint wear and tear, and acetaminophen to relieve the pain. Other types of arthritis (such as rheumatoid arthritis) are characterized by inflammation in the joint and therefore may require anti-inflammatory medications.

OA is the most common of all morbid conditions affecting the joints; its incidence increases with age. The condition is radiologically demonstratable in 68% of females and 58% of males, aged 65 or older. More than 70% of total knee and hip replacements are a direct result of OA.

According to established medical guidelines used by Canadian doctors, acetaminophen is recommended as the first-line therapy for patients with OA pain.

Osteoarthritis treatments generally fail to halt the progression of the disease. Therefore, OA therapy can be considered successful if it controls pain, maintains mobility, prevents the joints from stiffening and improves the quality of life.

Patients should be counselled to consult a physician if redness or swelling is present in the painful area; if symptoms worsen or do not improve; or if new symptoms such as high fever, rash or persistent headache occur. Any of these may be signs of a condition requiring medical attention. Acetaminophen should not be taken for pain for more than five days, or for fever for more than three days, unless directed by a physician. Tylenol products should not be taken with other products containing acetaminophen. Your patients may need help selecting other over-the-counter (OTC) products like cold preparations, some of which contain acetaminophen.

Acetaminophen is generally recognized as the OTC pain reliever of choice for patients on warfarin therapy. Unlike ASA and ibuprofen, it does not cause gastrointestinal bleeding, nor does it inhibit platelet aggregation critical to normal clotting. However, patients who concomitantly medicate with warfarin-type anticoagulants and regular doses of acetaminophen have occasionally experienced unforeseen elevations in their international normalized ratio (INR) measurements. Physiciansshould be aware of this potential interaction and monitor the INR in such patients. Tell these patients that it may be better for them to take the acetaminophen regularly, rather than intermittently, if this is appropriate.

Pharmacists can fulfill a very important role in advising patients of the problems of mixing alcohol with acetaminophen. Chronic heavy alcohol users–those who consume three or more alcohol drinks per day–may be at increased risk of liver toxicity from excessive doses of acetaminophen, although reports of this are rare. Acetaminophen can be taken with confidence by the occasional, moderate consumer of alcohol.

Every purchaser should be advised not to exceed the daily maximum of six caplets.

According to the National Kidney Foundation, acetaminophen is the nonprescription analgesic of choice for occasional use in patients with underlying kidney disease. Non-steroidal anti-inflammatory drugs may decrease blood flow to the kidneys in people with kidney disease.

McNeil has used a yellow box with blue lettering to distinguish this extended relief product from the rest of the Tylenol product line.

The SRPs for Tylenol Arthritis Pain Caplets are as follows: 24 caplets ($3.99), 50 caplets ($7.99), and 100 caplets ($11.99). The 100-size bottle has the easy-to-open cap commended by The Arthritis Society. This may not be appropriate when a child-resistant package is desired.

The McNeil Consumer Health-care help line is (800) 265-7323.

Stephanie Sinden is a pharmacist at Clark’s Health Centre Pharmacy in Simcoe, Ontario.