Some drugs are so common that consumers -- at their peril -- don't think twice about them. But each drug, whether prescription or over-the-counter, poses risks. To highlight these risks, we offer up a few details on five of the most-prescribed medications, with additional input from pharmacists interviewed for this package of stories.
Hydrocodone with acetaminophen
Brand names: Vicodin, Lortab
Description: A combination of a narcotic (hydrocodone) with a non-narcotic (acetaminophen) pain reliever, it's prescribed for moderate to severe pain.
Most serious risks: Abuse and addiction; acetaminophen overdose. Too much acetaminophen can cause severe liver damage, even death, but many patients aren't aware of this danger -- or of how many medications contain acetaminophen. Acetaminophen is the active ingredient in Tylenol, but it's also found in many other medications.
Possible side effects: Constipation, drowsiness, dizziness, nausea, vomiting, stomachache.
Common interactions: Barbiturate anesthetics (e.g., thiopental); cimetidine (Tagamet); antidepressants, including monoamine oxidase (MAO) inhibitors such as phenelzine (Nardil) and tricyclic antidepressants such as amitriptyline; sodium oxybate (GHB). These may lead to excessive sleepiness or create breathing difficulty.
And our pharmacists say . . . : This is probably one of the most abused drugs on the market. While taking this drug, avoid taking alcohol and other drugs that cause sleepiness. If you drive while taking it, you can be cited -- and convicted -- for driving under the influence. Check the labels of any other medications you are taking to see if they contain acetaminophen, and only take one source of acetaminophen at a time. Fluids and fiber can help prevent constipation, but you may also need to take laxatives. Taking this drug with food can reduce stomachache. The dizziness or drowsiness that can come with the drug can increase the risk of falls -- a serious danger for older people.
Brand names: Prinivil, Zestril
Description: An ACE (angiotensin-converting enzyme) inhibitor, lisinopril improves blood flow by interfering with the production of angiotensin II, a substance that constricts blood vessels and releases hormones that raise blood pressure. It's prescribed for high blood pressure and heart failure and to improve survival chances after heart attacks.
Most serious risks: Birth defects if taken while pregnant; hyperkalemia, a condition caused by high levels of potassium that can lead to an irregular heartbeat; nausea; slow, weak or nonexistent pulse; and even heart attacks. It is a particular risk in patients with poor kidney function.
Possible side effects: Nagging dry cough, dizziness. Less common but more severe: swelling of the face and lips, difficulty swallowing or breathing, itchiness.
Common interactions: Diuretics (may increase risk of low blood pressure); diabetes medications (may increase risk of low blood sugar); lithium (may increase lithium concentrations to toxic levels); potassium (may cause retention of potassium, so potassium supplements can lead to hyperkalemia); nonsteroidal anti-inflammatory drugs, such as ibuprofen or naproxen (these reduce the excretion of ACE inhibitors, so their concentration in the bloodstream increases).
And our pharmacists say . . . : This medication should never be used by pregnant women. ACE inhibitors are generally less potent in African Americans. Also, studies have shown that when taking lisinopril (or other ACE inhibitors), African Americans are at increased risk for angioedema (swelling similar to hives but under the skin and potentially life-threatening). Seniors too are at higher risk for angioedema. Also, if seniors are taking a diuretic and then start taking lisinopril too, their blood pressure may drop too quickly. It's better to start with lisinopril and add the diuretic later. If you drink alcohol while taking lisinopril, that can also make your blood pressure drop too much. Because lisinopril suppresses your body's ability to quickly adjust blood pressure, you could faint if you jump out of bed or stand up too fast. Avoid potassium supplements or salt substitutes containing potassium.
Brand name: Zocor
Description: Like other statins, simvastatin inhibits a particular liver enzyme (HMG Co-A reductase) to reduce the liver's capacity for making cholesterol. It's prescribed to reduce LDL cholesterol, often called "bad cholesterol."
Most serious risks: Birth defects if taken while pregnant; (rarely) rhabdomyolysis, a severe breakdown of skeletal muscle that can lead to acute renal failure and death should myoglobulin (a muscle protein) leak into the blood or urine (making urine dark).
Possible side effects: Constipation or diarrhea, upset stomach, mild muscle or joint pain.