Dear Savvy Senior: When is it safe, or not safe, to split pills? I have a cousin who cuts almost all her pills in half in order to save money, but I’m wondering if she’s going overboard. What can you tell me about this? — Curious Cousin

Dear Curious: Pill splitting — literally cutting them in half — has long been a popular way to save on medication costs. But if she hasn’t already done so, your cousin needs to talk to her doctor or pharmacist because not all pills should be split.

The reason pill splitting is such a money saver is because of the way drugs are manufactured and priced. A pill that’s twice as strong as another might not be twice the price. In fact, it’s usually about the same price.

That means buying a double-strength dose and cutting it in half might allow you to get two months’ worth of medicine for the price of one.

But is it safe? As long as your doctor agrees that splitting your pills is OK, and you learn to do it properly, there is really no danger.

Ask your doctor

If you’re interested in splitting your pills, start by talking to your doctor or pharmacist to find out which medicines you take can be safely split. It’s also important to calculate whether splitting them will save you enough money to justify the hassle.

The pills that are easiest to split are those with a score down the middle. Pills most commonly split are cholesterol-lowering drugs, antidepressants and high-blood-pressure medicines.

It’s important to note, however, that not every pill that’s scored is meant to be split.

Use a pill splitter

It’s important to know that pills are only safely split in half, never into smaller portions such as thirds or quarters.

Having the right equipment is extremely important. Don’t use a knife or scissors to cut your pills in half. That can cause you to split them unevenly, resulting in two pieces with very different dosages, which can be dangerous. Purchase a proper pill cutter that has a cover and a V-shaped pill grip that holds the pill securely in place. You can find them at most pharmacies for $5 to $10.

For convenience, you might be tempted to split the whole bottle of pills at once. But it’s best to do the splitting on the day you take the first half. That will help keep the drugs from deteriorating due to exposure to heat, moisture and air. It will also help ensure that any deviation in the size of one dose is compensated for in the next.

Don’t split these drugs

Some pills should never be split. Drugs that are time-released or long-lasting and tablets that contain a combination of drugs probably shouldn’t be split, because it’s difficult to ensure a proper amount of active ingredient in each half. Pills with a coating to protect your stomach, and pills that crumble easily or irritate your mouth shouldn’t be split either, along with chemotherapy drugs, anti- seizure medicines, birth control pills and capsules containing powders or gels.

Again, your doctor or pharmacist will know which drugs can and cannot be split. If you’re taking a medicine that can be split, you’ll need to get a prescription from your doctor for twice the dosage you need. Then you can start splitting and saving, safely.

Jim Miller is a contributor to NBC-TV’s “Today” program and author of “The Savvy Senior.” Send your questions to Savvy Senior, P.O. Box 5443, Norman, OK 73070; or visit savvysenior.org.