Drug Safety: Splitting Pills

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If you take prescription drugs to treat a chronic illness, you could save money by splitting your pills — literally cutting them in half. Not all pills can be split, so pill splitting cannot be used in the treatment of every chronic disease. But in the face of mounting costs for prescription drugs, many doctors and health authorities are advising this strategy with more and more medicines. Most notably, all the cholesterol-lowering drugs known as statins can be split as can many of the drugs used to treat high blood pressure and depression.

Essentially, pill splitting allows you to buy two doses of medicine for the price of one — or get two months’ worth of medicine for the price of one month. There is no danger in splitting pills as long as your doctor agrees that it’s a good idea for you, you learn how to do it properly, and you split only pills that can be split. Simple pill splitting devices are now widely available.


Doctors have long counseled patients to split their pills. Initially, this was not to save money. Instead, it was to enable people to take a dose of medicine not readily available from a pharmacist. That’s because drug companies make only a few fixed doses of any given medication. But many doctors prefer to tailor the dose of a medicine to a patient’s exact needs, or to lower the risk of side effects. For example, a doctor may want to prescribe less of a drug (say, 10mg) than the lowest dose available (say, 20mg).

A common example of pill splitting these days involves good old aspirin. Health authorities now urge anyone at risk for heart disease to take half an adult aspirin tablet a day. A regular aspirin tablet contains 325mg, but studies show that 160mg or less is just as good at lowering the risk of a heart attack or stroke — and safer. Some companies now make half-dose aspirin tablets and children’s aspirin comes in lower doses (generally 81mg). But often the least expensive alternative is to buy a large bottle of generic aspirin and split the pills in half.

Pill-splitting saves money because pharmaceutical companies and pharmacies often charge nearly the same amount for a particular medicine regardless of its dose. For example, a once-a-day drug may cost $100 for a month’s supply of both a 100mg dose and a 50mg dose. Thus, if your doctor prescribes the 50mg pill, it’ll cost you $100. But if he prescribes the 100mg pill and instructs you to cut it in half, $100 will buy you two months worth of medicine. If you take several medicines, that kind of savings can mount up.

Not surprisingly, many insurance companies are in favor of pill-splitting because it saves them money, too. Your employer may like the idea for the same reason. Some insurance companies now provide you with a list of approved drugs to split. And a few are even requiring pill-splitting by not covering the cost of some lower-dose drugs. This forces people to buy higher-dose pills and split them. The American Medical Association and the American Pharmacists Association oppose this practice. But these organizations acknowledge that many pills can be safely split if done correctly. The Department of Veteran’s Affairs allows pill splitting at a number of VA facilities, though it does not formally endorse the practice.

Most drug companies oppose pill-splitting. They say it can be dangerous. But studies to date have not shown any adverse impact on health. In addition, by reducing the cost of prescription medicines, pill splitting could improve health outcomes by helping people afford the drugs they need and comply with the drug regimens their doctors recommend.

Practical advice

Consult your doctor about pill splitting. The dose you take of most medicines is very important. If you don’t get the right dose, the effect of the drug may be substantially reduced. Your doctor should know which drugs can be split and which cannot. You can consult a pharmacist, too, who may be willing to show you how to split your pills.

Pills are only safely split in half and never into smaller portions, such as into thirds or quarters.

There is no official, complete list of medicines that can be split, and some drugs are dangerous to split. That makes it doubly important to consult a doctor or pharmacist. Generally the following kinds of pills should not be split:

  • Chemotherapy drugs
  • Anti-seizure medicines
  • Birth control pills
  • Blood thinners (Coumadin, warfarin)
  • Capsules of any kind that contain powders or gels
  • Pills with a hard outside coating
  • Pills designed to release the med- ication over time in your body
  • Pills that are coated to protect your stomach
  • Pills that provide drug release throughout the day
  • Pills that crumble easily, irritate your mouth, taste bitter, or contain strong dyes that could stain your teeth and your mouth.

Examples of medicines that cannot be split include oxycodone (OxyContin) for pain, omeprazole (Prilosec) for heartburn, and cetirizine (Zyrtec) for allergies.

Some pills may deteriorate when exposed to air and moisture for long periods after being split. Therefore, you should not split your pills in advance. Instead, do it on the day you are taking the first half. Then take the remaining half on the second day.

Don’t split your pills with a knife. This can be dangerous and generally is imprecise. That is, it leads to unequal halves too often, studies show. Instead, purchase a pill splitter. They cost from $3 to $10 and are available at most pharmacies and large discount stores. A device for splitting oddly shaped pills may cost more, up to $25. Some insurers will send you a pill splitter for free so check with your health plan.

If you have poor eyesight, or if you have an ailment like arthritis or Parkinson’s disease, it might be difficult for you to split your pills. You should talk with your doctor about whether it might be too much of a burden. Likewise, people with memory problems or impaired thinking are not good candidates to split their pills.

The easiest pills to split are relatively flat round ones with a scored center. That’s a slightly indented line that runs across the center of the pill. However, not every pill that has a scored center is meant to be split. Again, consult your doctor or pharmacist.


  • Amlodipine (Norvasc)
  • Atenolol (Tenormin)
  • Atorvastatin (Lipitor)
  • Citalopram (Celexa)
  • Clonazepam (Klonopin)
  • Doxazosin (Cardura)
  • Finasteride (Proscar)
  • Levothyroxine (Synthroid)
  • Lisinopril (Zestril)
  • Lovastatin (Mevacor)
  • Metformin (Glucophage)
  • Metoprolol (Toprol)
  • Nefazodone (Serzone)
  • Olanzapine (Zyprexa)
  • Paraxetine (Paxil)
  • Pravastatin (Pravachol)
  • Quinapril (Accupril)
  • Rosuvastatin (Crestor)
  • Sertraline (Zoloft)
  • Sildenafil (Viagra)
  • Simvastatin (Zocor)
  • Tadafil (Cialis) 
  • Vardenafil (Levitra)

THE SHOPPER’S GUIDE TO PRESCRIPTION DRUGS SERIES: This series is produced by Consumers Union and Consumer Reports Best Buy Drugs, a public information project supported by grants from the Engelberg Foundation and the National Library of Medicine of the National Institutes of Health. The project’s free Web site is www.CRBestBuyDrugs.org. This brief should not be viewed as a substitute for a consultation with a med- ical or health professional. It is provided to enhance communication with your doctor, not replace it. Neither the National Library of Medicine nor the National Institutes of Health are responsible for the content or advice herein.