Is it safe to cut a tablet in half?

Can Tablets Be Cut in Half?

Whether a tablet can be safely cut in half depends entirely on its formulation—scored tablets designed for splitting can be divided, but extended-release, enteric-coated, or unscored tablets should never be split due to serious risks of overdose, loss of efficacy, and adverse reactions. 1, 2

When Tablet Splitting Is Appropriate

Acceptable Scenarios

• Scored tablets specifically designed for splitting can be divided to achieve dose flexibility, particularly useful in geriatric and pediatric populations where standard strengths may not match individual requirements 2
• Phentermine tablets are explicitly mentioned as suitable for splitting—a quarter tablet (9.375 mg) or half tablet (18.75 mg) may be adequate for some patients, and a split dose of half a tablet twice daily is also an option 3
• Chloroquine and hydroxychloroquine can be split to achieve intermediate doses, as blood levels stabilize over weeks and variable dosing averages out over time—this can be accomplished by splitting tablets or eliminating a tablet on certain days of the week 3

Clinical Benefits

• Increases dose flexibility for individualized dosing 2
• Makes large tablets easier to swallow 2, 4
• Reduces medication costs when higher-strength tablets are split 2

When Tablet Splitting Is Dangerous

Absolute Contraindications

• Extended-release formulations: Splitting destroys the controlled-release mechanism, causing uncontrolled release of the active component and potential overdose 1, 2
• Enteric-coated tablets: Breaking the coating leads to premature drug degradation from gastric acid and loss of therapeutic effect 1, 2
• Unscored tablets: These are not designed for splitting and result in unequal doses 2, 5
• Capsules: Should never be split or opened unless specifically instructed 5

Specific Examples from Guidelines

• Tuberculosis medications: First-line antituberculosis drugs must be administered together and split dosing should be avoided 3
• Pancreatic enzyme preparations: Enteric-coated formulations must not be split, as the coating protects enzymes from gastric acidity 3

Critical Safety Considerations

Dosing Accuracy Issues

• Even with appropriate splitting methods, significant dose deviations occur—this is particularly dangerous for medications with narrow therapeutic-toxic ranges 4
• A study found that 10% of split tablets in ambulatory settings were inappropriate (lacking score lines or having protective coatings that were destroyed) 5
• Mean weight deviations and weight loss during splitting can be substantial, even with proper splitting devices 4

Best Practices When Splitting Is Necessary

• Use a tablet splitting device rather than scissors or knives, as this produces significantly lower mean deviation from theoretical weight and less weight loss 4
• Verify the tablet has a score line and is designed for splitting 2
• Assess the patient's ability and willingness to split tablets correctly—the majority of elderly patients are not capable of breaking tablets properly 2
• Consider light-sensitive compounds that may degrade when exposed after splitting 2

Alternative Approaches

Preferred Options Over Splitting

• Request prescriptions for lower-strength tablets that match the desired dose 5
• Use liquid formulations when available 5
• Consider fixed-dose combination preparations that eliminate the need for splitting 3

Patient Education Requirements

• Patients should never split or crush medications without explicit approval from their healthcare provider or pharmacist 1
• Proper instruction on splitting technique is essential if splitting is deemed necessary 2
• Patients must understand that storing split tablets exposes them to environmental factors that compromise stability and safety 6

Common Pitfalls to Avoid

• Never assume all scored tablets are safe to split—some scored tablets are still unsuitable for the intended fragmentation 5
• Do not split tablets to save money without first confirming the specific medication is appropriate for splitting 2, 6
• Avoid splitting for patients with swallowing difficulties without considering liquid alternatives, as split tablets may still pose choking hazards 2
• Do not store split tablet portions in pill organizers for extended periods, as this exposes medications to humidity, light, and temperature changes that degrade the drug 6