Can Desvenlafaxine ER Tablets Be Split?
No, desvenlafaxine extended-release tablets must not be split, crushed, chewed, or dissolved—they must be swallowed whole with fluid. 1
Critical Administration Requirements
The FDA-approved drug label explicitly states that patients must "swallow desvenlafaxine tablets whole, with fluid" and "do not divide, crush, chew, or dissolve desvenlafaxine tablets." 1 This is a non-negotiable requirement for extended-release formulations.
Why Splitting Is Contraindicated
Extended-release formulations are specifically engineered to deliver medication over an extended period through specialized tablet matrices. 1 When you split, crush, or chew these tablets, you:
- Destroy the controlled-release mechanism, causing immediate release of the entire dose 1
- Create risk of dose dumping, which can lead to serious adverse effects including serotonin syndrome, severe hypertension, and other potentially life-threatening complications 1
- Lose the pharmacokinetic advantage of once-daily dosing that desvenlafaxine ER provides through its sufficiently long elimination half-life 2, 3
What Patients May Observe
After taking desvenlafaxine ER whole, patients may see something in their stool that looks like a tablet—this is the empty shell from the tablet after the medicine has been absorbed by the body and is completely normal. 1 This ghost tablet appearance does not indicate treatment failure.
Dosing Flexibility Without Splitting
Desvenlafaxine ER requires no dose titration, unlike venlafaxine immediate-release. 3 The medication is available in multiple tablet strengths, allowing dose adjustments by changing to a different tablet strength rather than splitting tablets. 4, 5
The recommended therapeutic dose range is 50-100 mg once daily, with no additional benefit shown at higher dosages and significantly higher risk of side effects at 400 mg/day. 5, 6
Common Pitfall to Avoid
Never attempt to split extended-release tablets to achieve lower doses or save costs—this practice compromises both safety and efficacy. 1 If dose adjustment is needed, prescribe a different tablet strength rather than instructing patients to split tablets.