Apremilast: what it treats, how to take it, side effects
Last updated September 3, 2026.
Apremilast (brand name Otezla) is an oral PDE4 inhibitor for plaque psoriasis, psoriatic arthritis, and the mouth ulcers of Behcet's disease. It is the non-injection option in its class: a pill, no lab monitoring required, with a gentler immune footprint than biologics.
What does it treat?
It treats moderate to severe plaque psoriasis and active psoriatic arthritis in adults, and oral ulcers in Behcet's disease. It works inside immune cells by inhibiting phosphodiesterase 4, which dials down inflammatory signaling. It is not immunosuppressive in the way biologics or cyclosporine are, which is why no routine blood monitoring is required.
How do you take it?
Treatment ramps over 5 days to reduce stomach upset, then continues at 30 mg twice daily (an extended-release 75 mg once-daily option also exists). Take it at the same times daily, with or without food, and swallow tablets whole, never split, chewed, or crushed. If you miss a dose, take it when remembered unless the next dose is near, and never double up. Stomach side effects are worst in the first two weeks and usually fade; sticking through the titration week is the trick.
Side effects to know
- Common: diarrhea, nausea, vomiting, upper respiratory infections, tension headaches, and headache, concentrated in the first weeks.
- Serious: the label warns about depression, including worsening depression and suicidal thinking, and about weight loss, which should be monitored. Severe or persistent vomiting and diarrhea can dehydrate, especially in older patients.
Who should not take it?
Do not use it with a known hypersensitivity to apremilast. Tell your prescriber about any history of depression, mood problems, or suicidal thoughts, and about kidney disease, since severe renal impairment changes the dose. Strong CYP450 inducers like rifampin, phenobarbital, carbamazepine, phenytoin, and St. John's wort can make it fail. Use in pregnancy or breastfeeding is a decision for your doctor.
When is it an emergency?
If thoughts of harming or killing yourself appear while taking apremilast, call or text 988 (the Suicide and Crisis Lifeline in the US) immediately, or your local crisis line elsewhere, and contact your prescriber. Swelling of the face or throat or trouble breathing after a dose means call 911. Pymander's escalation routing is built and tested specifically for this class of decision; see the safety architecture working paper.
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Common questions
Why does the first week use a ramp-up schedule?
The 5-day titration exists to reduce the diarrhea, nausea, and vomiting that hit hardest when the drug starts. Skipping the ramp makes those first weeks rougher without getting you to the target dose any faster, so follow the day-by-day schedule in the starter pack.
Does apremilast suppress the immune system?
Only modestly. It tunes down inflammatory signaling inside immune cells rather than broadly suppressing immunity the way biologics, methotrexate, or cyclosporine do. That is why no routine lab monitoring is required and why it is often picked by people who cannot tolerate stronger immunosuppression.
Will apremilast make me lose weight?
It can. Weight decrease is a labeled warning, and your prescriber should check your weight periodically. Modest loss is common; unexplained or rapid loss gets evaluated and may mean stopping. It is not a weight-loss drug, and using it as one is not what it is for.
What is the depression warning about?
The label warns about depression, including new or worsening depression and suicidal thoughts. Tell your prescriber about any mood history before starting, and report mood changes while on it. Thoughts of self-harm mean call or text 988 in the US immediately and contact your prescriber.
How long until my skin improves?
Give it 12 to 16 weeks for a fair trial on skin, which is when trials measured response; joint symptoms often move sooner. It is a moderate-efficacy, high-convenience drug: many get meaningful clearing, few get total clearance, and no response by 4 months is a reason to reconsider.
Can I take apremilast with methotrexate or a biologic?
It is sometimes combined with methotrexate or other agents under specialist care, but do not stack immunomodulators on your own. The big no is strong CYP450 inducers like rifampin and St. John's wort, which cut apremilast levels enough to make it fail.