In medical terms, “tab” is shorthand for tablet. It comes from the Latin word tabella and appears on prescriptions, medication labels, and medical records to indicate that a drug comes in solid tablet form. If you’ve seen “tab” on a prescription bottle or in a doctor’s note, that’s all it means.
How “Tab” Appears on Prescriptions
“Tab” rarely shows up alone. It’s usually embedded in a string of abbreviations that together tell you exactly how to take your medication. A prescription might read something like “1 tab PO BID,” which translates to “take one tablet by mouth twice a day.” Here are the abbreviations you’ll most commonly see paired with “tab”:
- PO: by mouth (from the Latin per os)
- BID: twice a day
- TID: three times a day
- QID: four times a day
- PRN: as needed
- QHS: before bed
- AC: before meals
- PC: after meals
- Q6H: every six hours
So “2 tabs PO TID PC” means “take two tablets by mouth three times a day after meals.” Once you know the building blocks, these shorthand strings become straightforward to decode.
What a Tablet Actually Is
A tablet is made by compressing powdered ingredients into a hard, solid form. Beyond the active drug, most tablets contain inactive additives that hold the pill together, improve its taste, or give it a smooth coating. Tablets break down in your digestive tract, where the medication is absorbed into your bloodstream.
Compared to capsules (abbreviated “cap”), tablets tend to absorb more slowly. Capsules break down faster and generally deliver more of the drug into your system. On the other hand, tablets are cheaper to manufacture, which often makes them the more affordable option at the pharmacy. Tablets can also be scored for splitting, something capsules can’t do.
Scored Tablets and Splitting
Some tablets have a debossed line running across the surface, called a score line. This line exists so you can split the tablet into smaller doses. A scored 20 mg tablet, for example, can give you two 10 mg doses.
Not every tablet with a line is safe to split, though. The FDA evaluates scored tablets against specific criteria: each split portion must contain a consistent amount of the drug, remain stable for at least 90 days after splitting, and meet the same quality standards as a whole tablet of the equivalent strength. Extended-release or other modified-release tablets should not be scored at all, because splitting them can compromise the way the drug is released into your body. If your tablet doesn’t have a score line, assume it’s not meant to be divided.
Specialized Tablet Types
Not all tablets work the same way. You’ll sometimes see additional letters after “tab” on a prescription label that indicate a specialized formulation.
Extended-Release (ER or XR)
These tablets release medication gradually over many hours instead of all at once. This means fewer doses per day and steadier drug levels in your bloodstream. You should never crush or break an extended-release tablet, because doing so dumps the entire dose at once, which can be dangerous.
Enteric-Coated (EC)
Enteric-coated tablets have a special outer layer that resists stomach acid. The tablet passes through the stomach intact and only dissolves once it reaches the intestine. This protects drugs that would break down in the acidic stomach environment, like certain heartburn medications, and also reduces stomach irritation from drugs like naproxen. Crushing or chewing an enteric-coated tablet defeats the entire purpose of the coating.
Orally Disintegrating (ODT)
These tablets dissolve on your tongue within seconds, no water needed. Because the drug starts absorbing through the lining of your mouth and throat before it even reaches the stomach, ODTs can work faster than conventional tablets. They also bypass the liver’s first pass of metabolism, which means more of the drug reaches your system. ODTs are especially useful for children, people who have difficulty swallowing, and situations where you need rapid relief.
Taking Tablets Safely
The general rule is to swallow tablets whole with water. Don’t crush, break, or chew a tablet unless your pharmacist or prescriber has specifically told you it’s safe to do so. This is especially critical for extended-release and enteric-coated formulations, where altering the tablet can cause too much medication to release at once or allow stomach acid to destroy the drug before it works.
If you have trouble swallowing tablets, ask your pharmacist whether your specific medication is available as an ODT, a liquid, or a capsule that can be opened and mixed with food. There’s often an alternative form available, but the switch needs to be confirmed for your particular drug rather than assumed.