Drug Monograph

Daliresp (Roflumilast)

roflumilast — selective phosphodiesterase 4 (PDE4) inhibitor

Selective PDE4 Inhibitor · Oral Tablet · Pulmonology
Pharmacokinetic Profile
Half-Life
~17 h (parent); ~30 h (N-oxide metabolite)
Metabolism
CYP3A4 + CYP1A2 → roflumilast N-oxide (active)
Protein Binding
~99% (parent); ~97% (N-oxide)
Bioavailability
~80% (oral)
Volume of Distribution
~2.9 L/kg
Clinical Information
Drug Class
Selective PDE4 inhibitor
Available Doses
250 mcg tablet; 500 mcg tablet
Route
Oral
Renal Adjustment
Not required
Hepatic Adjustment
Child-Pugh B/C: Contraindicated; A: Use with caution
Pregnancy
No adequate human data; animal: post-implantation loss, stillbirth
Lactation
Not recommended (excreted in rat milk)
Schedule
Rx only (not controlled)
Generic Available
Yes
Rx

Indications

Roflumilast is the first oral PDE4 inhibitor approved for COPD. It occupies a unique niche as a non-bronchodilator, anti-inflammatory oral add-on therapy that targets the PDE4 enzyme predominantly expressed in lung tissue. Its clinical benefit is specifically in reducing exacerbation frequency in a well-defined COPD subpopulation: patients with severe disease, chronic bronchitis phenotype, and a history of exacerbations.

IndicationApproved PopulationTherapy TypeStatus
Reduce risk of COPD exacerbations in severe COPD associated with chronic bronchitis and a history of exacerbationsAdultsAdd-on maintenance (not a bronchodilator)FDA Approved

Roflumilast is not a bronchodilator and must not be used for acute bronchospasm relief. The 250 mcg tablet is a starting dose only and is not the effective therapeutic dose. The GOLD guidelines position roflumilast as a potential add-on for patients with frequent exacerbations despite triple inhaled therapy (ICS/LABA/LAMA), particularly those with blood eosinophils <100 cells/µL or the chronic bronchitis phenotype.

Off-Label Uses

Asthma — Earlier clinical trials evaluated roflumilast in asthma, showing modest improvements in FEV1 and symptom control when added to ICS. Not FDA-approved for asthma; the FDA limited approval to COPD. Evidence quality: moderate.

Dose

Dosing

Clinical ScenarioStarting DoseMaintenance DoseMaximum DoseNotes
Severe COPD with chronic bronchitis — exacerbation prevention250 mcg PO once daily × 4 weeks500 mcg PO once daily500 mcg/dayWith or without food; 250 mcg is NOT the therapeutic dose
4-week uptitration reduces early GI discontinuation
Severe COPD — add-on to triple inhaled therapy (ICS/LABA/LAMA)250 mcg PO once daily × 4 weeks500 mcg PO once daily500 mcg/dayContinue all background COPD therapy
REACT trial evaluated this combination (FDA PI Trial 9)
Mild hepatic impairment (Child-Pugh A)Use with cautionWeigh risk vs benefit500 mcg/dayAUC of roflumilast increased 51%; N-oxide increased 24%
No specific dose reduction recommended but monitor closely
Clinical Pearl — The 4-Week Uptitration

The 250 mcg starting dose for 4 weeks is designed to improve early tolerability, not for efficacy. The main drivers of treatment discontinuation are gastrointestinal effects (diarrhea and nausea), which peak during the first weeks. In a dedicated titration trial, starting at 250 mcg before escalating to 500 mcg reduced early dropout rates. However, 250 mcg does not provide meaningful exacerbation prevention and must not be continued beyond 4 weeks as the sole dose. Taking roflumilast with food may also help minimize nausea, although food does not change total drug absorption.

PK

Pharmacology

Mechanism of Action

Roflumilast and its active metabolite, roflumilast N-oxide, are selective inhibitors of phosphodiesterase 4 (PDE4), the predominant cyclic AMP (cAMP)-metabolizing enzyme in lung tissue and inflammatory cells. By blocking PDE4, roflumilast prevents the hydrolysis of cAMP to AMP, leading to intracellular accumulation of cAMP. Elevated cAMP levels suppress the activation and proliferation of key inflammatory cells involved in COPD pathogenesis, including neutrophils, eosinophils, macrophages, and T lymphocytes. In clinical pharmacodynamic studies, roflumilast reduced sputum neutrophils by 31% and eosinophils by 42% after 4 weeks of treatment. While the precise therapeutic mechanism in COPD is not fully defined, the net effect is a broad anti-inflammatory action in the airways that reduces exacerbation frequency without producing direct bronchodilation. Notably, roflumilast N-oxide circulates at approximately 10-fold higher plasma concentrations than the parent compound and, despite being about one-third as potent as roflumilast at PDE4 inhibition, contributes substantially to overall pharmacological activity.

ADME Profile

ParameterValueClinical Implication
AbsorptionBioavailability ~80%; Tmax ~1 h (parent, fasted), ~8 h (N-oxide); food delays Tmax by ~1 h and reduces parent Cmax by ~40% but does not affect total absorption or N-oxide CmaxCan be taken with or without food; taking with food may reduce nausea without compromising efficacy; rapid oral absorption
DistributionVd ~2.9 L/kg; protein binding ~99% (parent), ~97% (N-oxide); low CNS penetration (animal data)High protein binding makes hemodialysis ineffective for overdose; wide tissue distribution but limited BBB crossing despite psychiatric side effects
MetabolismExtensive Phase I (CYP3A4 + CYP1A2 → N-oxide, the only major active metabolite) and Phase II (conjugation); parent + N-oxide account for 87.5% of circulating drug; N-oxide AUC ~10-fold higher than parentDual CYP pathway explains susceptibility to both CYP3A4 and CYP1A2 inhibitors/inducers; strong inducers (rifampicin) reduce total PDE4 inhibition by 58% and are not recommended
Eliminationt½ ~17 h (parent), ~30 h (N-oxide); plasma clearance ~9.6 L/h (IV); ~70% recovered in urine (as metabolites); steady state ~4 days (parent), ~6 days (N-oxide)N-oxide half-life of 30 hours drives effective duration of PDE4 inhibition; once-daily dosing is appropriate; no renal dose adjustment needed even in severe impairment
SE

Side Effects

≥5% Very Common
Adverse EffectIncidenceClinical Note
Diarrhea9.5% vs 2.7% placeboMost common AE and top reason for discontinuation (2.4%); usually occurs early; may improve with 4-week uptitration; taking with food may help
Weight decreased7.5% vs 2.1% placebo20% experienced moderate loss (5–10% body weight) vs 7% placebo; 7% experienced severe loss (>10%) vs 2% placebo; mostly regained after discontinuation; monitor regularly
2–5% Common
Adverse EffectIncidenceClinical Note
Nausea4.7% vs 1.4% placeboSecond most common cause of discontinuation (1.6%); often transient; improves with food and uptitration
Headache4.4% vs 2.1% placeboUsually mild; resolves without treatment change
Back pain3.2% vs 2.2% placeboNon-specific musculoskeletal complaint; marginally above placebo
Influenza2.8% vs 2.7% placeboNot significantly different from placebo
Insomnia2.4% vs 1.0% placeboPart of the psychiatric AE cluster; consider taking roflumilast in the morning if sleep is affected
Dizziness2.1% vs 1.1% placeboGenerally mild and self-limiting
Decreased appetite2.1% vs 0.4% placeboContributes to weight loss; monitor nutritional status in underweight patients
Serious Serious (Regardless of Frequency)
Adverse EffectEstimated FrequencyTypical OnsetRequired Action
Suicidal ideation and behavior (including completed suicide)Rare (3 cases vs 1 placebo in trials; postmarketing reports)Variable; can occur at any time during treatmentCarefully weigh risks/benefits before prescribing in patients with depression history; advise patients, caregivers, families to report mood changes; consider discontinuation
Psychiatric adverse reactions (total cluster: insomnia, anxiety, depression)5.9% vs 3.3% placeboWeeks to monthsMonitor for emergence or worsening; depression 1.2% vs 0.9%, anxiety 1.4% vs 0.9%; evaluate risk-benefit if symptoms emerge
Clinically significant weight loss (>10% body weight)7% vs 2% placeboGradual over weeks to monthsMonitor weight regularly; evaluate unexplained or significant weight loss; consider discontinuation
Hypersensitivity reactions (angioedema, urticaria, rash)Rare (postmarketing)VariableDiscontinue; appropriate symptomatic treatment
Acute pancreatitisRare (reported more frequently in roflumilast vs placebo)VariableDiscontinue; standard pancreatitis management
Discontinuation Discontinuation Rates
Overall (8 Controlled Trials)
14.8% vs 9.9% placebo
Top reasons: Diarrhea (2.4%), nausea (1.6%)
With 4-Week Uptitration
Lower vs direct 500 mcg start
Rationale: 250 mcg × 4 weeks before 500 mcg reduces early GI-driven discontinuation
Managing GI Side Effects — The Most Clinically Relevant Challenge

Diarrhea affects nearly 1 in 10 patients and is the primary driver of treatment dropout. Practical strategies include the 4-week uptitration from 250 mcg, taking the tablet with food, and counselling patients that GI effects often diminish over the first 4–8 weeks. Patients who are underweight, cachectic, or at nutritional risk should be monitored especially closely, as the combination of decreased appetite, nausea, and diarrhea can compound the weight loss that already affects 7.5% of treated patients.

Int

Drug Interactions

Roflumilast is extensively metabolized by CYP3A4 and CYP1A2 to its active N-oxide metabolite, making it susceptible to both enzyme inducers and inhibitors. Roflumilast itself does not inhibit or induce CYP enzymes at therapeutic concentrations, so it poses minimal risk of affecting the levels of other drugs. No significant interactions were observed with commonly co-administered COPD medications (salbutamol, formoterol, budesonide, montelukast, theophylline) or with digoxin, warfarin, sildenafil, midazolam, or antacids.

Major Strong CYP Inducers (rifampicin, phenobarbital, carbamazepine, phenytoin)
MechanismInduce CYP3A4 metabolism of roflumilast, dramatically reducing exposure
EffectRifampicin reduced roflumilast AUC by 79% and total PDE4 inhibitory activity by 58%
ManagementCo-administration is NOT recommended; therapeutic effectiveness may be lost
FDA PI
Moderate CYP3A4 Inhibitors (erythromycin, ketoconazole)
MechanismInhibit CYP3A4-mediated conversion to N-oxide, increasing parent drug exposure
EffectErythromycin: AUC ↑70%; Ketoconazole: AUC ↑99% (parent); overall PDE4 inhibition modestly increased
ManagementWeigh risk of increased adverse effects against benefit; monitor for GI and psychiatric side effects
FDA PI
Moderate Dual CYP3A4/1A2 Inhibitors (fluvoxamine, cimetidine, enoxacin)
MechanismInhibit both metabolic pathways simultaneously, causing the greatest increase in roflumilast exposure
EffectFluvoxamine: parent AUC ↑156%; Cimetidine: parent AUC ↑85%; Enoxacin: parent AUC ↑56%
ManagementCarefully weigh risk vs benefit; fluvoxamine poses particular concern given additive psychiatric risk
FDA PI
Moderate Oral Contraceptives (gestodene/ethinyl estradiol)
MechanismGestodene-containing OCs increase roflumilast exposure via CYP inhibition
EffectRoflumilast AUC ↑51%; N-oxide AUC ↑14%
ManagementWeigh risk vs benefit; monitor for increased adverse effects
FDA PI
Minor Inhaled COPD Medications (salbutamol, formoterol, budesonide)
MechanismNo pharmacokinetic interaction identified
EffectNo clinically significant change in roflumilast or co-administered drug levels
ManagementContinue all background COPD therapy; no dose adjustment needed
FDA PI
Minor Theophylline, Warfarin, Digoxin, Sildenafil, Montelukast, Antacids
MechanismNo significant pharmacokinetic interaction
EffectRoflumilast does not significantly alter levels of these medications
ManagementNo dose adjustment required for either drug
FDA PI
Mon

Monitoring

  • Body Weight Baseline, monthly × 3 months, then Q3 months
    Routine
    Weight loss affects 7.5% of patients (vs 2.1% placebo); 7% experience >10% body weight loss. Monitor regularly. If unexplained or clinically significant weight loss occurs, evaluate the cause and consider discontinuation. Most patients regain weight after stopping roflumilast.
  • Psychiatric Status Each visit; advise caregivers
    Routine
    Psychiatric AEs occurred in 5.9% of patients (vs 3.3% placebo). Ask about new or worsening insomnia, anxiety, depression, suicidal thoughts, or behavioral changes at every visit. Advise patients, caregivers, and families to be alert and report mood changes promptly. Evaluate risk-benefit if symptoms emerge.
  • GI Tolerability Weeks 1–4 (during uptitration)
    Routine
    Diarrhea (9.5%) and nausea (4.7%) are most common during the first few weeks. Counsel patients that these often improve with continued use. If intolerable, consider discontinuation rather than dose reduction below the therapeutic 500 mcg.
  • Liver Function Baseline
    Routine
    Roflumilast is contraindicated in moderate-to-severe hepatic impairment (Child-Pugh B/C). Assess liver status before initiating therapy. Use with caution in mild impairment (Child-Pugh A) given 51% increase in parent AUC.
  • Exacerbation Frequency Q3–6 months
    Routine
    Assess whether roflumilast is achieving its intended goal of reducing COPD exacerbations. If exacerbation frequency has not decreased after 6–12 months, reassess continued use given the side effect burden.
  • Drug Interactions At initiation and medication changes
    Trigger-based
    Review medication list for strong CYP inducers (contraindicated with roflumilast) and CYP3A4/1A2 inhibitors (which increase exposure and adverse effects). Fluvoxamine is of particular concern given combined CYP inhibition and additive psychiatric risk.
CI

Contraindications & Cautions

Absolute Contraindications

  • Moderate to severe hepatic impairment (Child-Pugh B or C) — roflumilast AUC increases by 92% in Child-Pugh B subjects; 500 mcg has not been studied in these patients. Risk of toxicity is unacceptable.

Relative Contraindications (Specialist Input Recommended)

  • Active major depression or history of suicidal ideation/behavior — roflumilast is associated with psychiatric adverse events including completed suicide. Carefully weigh risks and benefits before prescribing in patients with a history of depression, psychiatric illness, or suicidality. This is not a labelled absolute contraindication but requires documented risk-benefit assessment.
  • Concurrent use with strong CYP inducers (rifampicin, phenobarbital, carbamazepine, phenytoin) — reduces roflumilast exposure by up to 79% and total PDE4 inhibition by 58%, potentially eliminating therapeutic benefit. The PI states co-administration is not recommended.

Use with Caution

  • Mild hepatic impairment (Child-Pugh A) — AUC of roflumilast increased by 51% and N-oxide by 24%. No specific dose reduction exists; weigh risk versus benefit.
  • Underweight or cachectic patients — given the 7.5% incidence of weight loss (and 7% with >10% body weight loss), roflumilast should be used cautiously in patients who are already underweight or malnourished. Monitor nutritional status closely.
  • Concurrent CYP3A4/1A2 inhibitors — fluvoxamine increases roflumilast AUC by 156%, posing both pharmacokinetic and pharmacodynamic risk (additive psychiatric effects). Carefully weigh risk vs benefit with any dual CYP inhibitor.
  • Pregnancy — no adequate human data. Animal studies showed post-implantation loss at ≥10× MRHD, stillbirth and decreased pup viability at ≥16× MRHD. Not teratogenic. Avoid use during labor and delivery (disrupted labor in mice).
  • Lactation — not recommended. Roflumilast and/or its metabolites are excreted in rat milk; excretion into human milk is probable.
  • Geriatric patients — AUC ~27% higher in elderly (>65 years) vs young; no dose adjustment needed but be aware of increased exposure. 2,022 of 4,438 trial patients were >65 years; no overall safety differences observed.
FDA Safety Advisory Psychiatric Events Including Suicidality

Roflumilast does not carry a formal FDA Boxed Warning, but the Warnings and Precautions section prominently addresses psychiatric adverse reactions. In 8 controlled clinical trials, 5.9% of roflumilast-treated patients reported psychiatric adverse reactions versus 3.3% on placebo. Three patients on roflumilast experienced suicide-related events (one completed suicide, two attempts) compared to one patient (suicidal ideation) on placebo. Postmarketing cases of suicidal ideation, behavior, and completed suicide have also been reported in patients with and without a history of depression. Prescribers must assess psychiatric risk before initiation and monitor throughout treatment.

Pt

Patient Counselling

Purpose of Therapy

Roflumilast is a daily oral tablet that works by reducing inflammation in the airways. It is designed to prevent COPD flare-ups (exacerbations) over the long term, particularly in patients with the chronic bronchitis type of COPD who have a history of flare-ups. It is not a bronchodilator and will not open your airways quickly during an acute breathing episode. Continue all your usual inhalers and rescue medications as prescribed.

How to Take

Take one tablet once daily, with or without food. You will start with a lower-strength tablet (250 mcg) for the first 4 weeks, then switch to the full-strength tablet (500 mcg) from week 5 onwards. The lower-strength tablet is just a starting dose to help your body adjust and reduce stomach upset; it does not treat your COPD. Taking the tablet with food may help reduce nausea or diarrhea. You can take it at any time of day, but taking it in the morning may help if you experience trouble sleeping.

Diarrhea and Nausea
Tell patientDiarrhea and nausea are common when starting roflumilast, especially during the first few weeks. These symptoms often improve with continued use. Taking the tablet with food and starting at the lower dose for 4 weeks helps reduce these effects. Stay hydrated if you experience diarrhea.
Call prescriberIf diarrhea is severe, persistent, or accompanied by blood; if nausea prevents you from eating; or if you develop significant abdominal pain.
Weight Changes
Tell patientSome patients lose weight while taking roflumilast. Weigh yourself regularly (at least monthly). Most weight loss that occurs on roflumilast is regained after stopping the medication.
Call prescriberIf you notice unexpected or significant weight loss, loss of appetite, or if you are losing more than 5% of your body weight.
Mood and Mental Health Changes
Tell patientRoflumilast can occasionally cause changes in mood or behavior, including trouble sleeping, anxiety, or feelings of depression. In rare cases, it has been associated with thoughts of self-harm. It is important that you, your family, and caregivers are aware of this possibility and watch for any changes.
Call prescriberImmediately if you experience new or worsening depression, anxiety, restlessness, trouble sleeping that does not improve, thoughts of harming yourself, or any unusual changes in mood or behavior.
Not a Rescue Medication
Tell patientRoflumilast does not open your airways and will not help during an acute breathing emergency. Always keep your rescue inhaler (e.g., albuterol) available and continue all prescribed inhalers.
Call prescriberIf your breathing problems are getting worse, you are using your rescue inhaler more often, or you have a COPD flare-up despite taking roflumilast.
Ref

Sources

Regulatory (PI / SmPC)
  1. Daliresp (roflumilast) tablets. Full Prescribing Information. AstraZeneca Pharmaceuticals LP. Revised 01/2018. https://www.accessdata.fda.gov/drugsatfda_docs/label/2018/022522s009lbl.pdf Primary source for all dosing, indications, adverse reactions, warnings, pharmacokinetic data, drug interactions, and clinical trial summaries in this monograph.
Key Clinical Trials
  1. Calverley PMA, Sanchez-Toril F, McIvor A, et al. Effect of 1-year treatment with roflumilast in severe chronic obstructive pulmonary disease. Am J Respir Crit Care Med. 2007;176(2):154-161. doi:10.1164/rccm.200610-1563OC One of the earliest pivotal 1-year trials demonstrating roflumilast efficacy in reducing COPD exacerbation rates.
  2. Calverley PMA, Rabe KF, Goehring U-M, et al. Roflumilast in symptomatic chronic obstructive pulmonary disease: two randomised clinical trials. Lancet. 2009;374(9691):685-694. doi:10.1016/S0140-6736(09)61255-1 M2-124 and M2-125 replicate trials; demonstrated 17% exacerbation reduction in the chronic bronchitis with history of exacerbations subgroup that defined the FDA-approved indication.
  3. Fabbri LM, Calverley PMA, Izquierdo-Alonso JL, et al. Roflumilast in moderate-to-severe chronic obstructive pulmonary disease treated with long-acting bronchodilators: two randomised clinical trials. Lancet. 2009;374(9691):695-703. doi:10.1016/S0140-6736(09)61252-6 Demonstrated roflumilast efficacy when added to salmeterol or tiotropium; supported the add-on role in COPD management.
  4. Martinez FJ, Calverley PMA, Goehring U-M, et al. Effect of roflumilast on exacerbations in patients with severe chronic obstructive pulmonary disease uncontrolled by combination therapy (REACT): a multicentre randomised controlled trial. Lancet. 2015;385(9971):857-866. doi:10.1016/S0140-6736(14)62410-7 REACT trial evaluating roflumilast added to ICS/LABA in severe COPD; source for Trial 9 safety and efficacy data referenced in the PI.
  5. Watz H, Bagul N, Rabe KF, et al. Use of a 4-week up-titration regimen of roflumilast in patients with severe COPD. Int J Chron Obstruct Pulmon Dis. 2018;13:813-822. doi:10.2147/COPD.S154012 Dedicated titration trial supporting the 250 mcg × 4 weeks starting dose to reduce early GI-driven discontinuation.
Guidelines
  1. Global Initiative for Chronic Obstructive Lung Disease (GOLD). Global Strategy for the Prevention, Diagnosis, and Management of COPD. 2025 Report. https://goldcopd.org/gold-reports/ Current GOLD guideline positioning roflumilast as an add-on option for Group E patients with persistent exacerbations despite triple inhaled therapy, particularly with chronic bronchitis phenotype.
Mechanistic / Basic Science
  1. Rabe KF. Update on roflumilast, a phosphodiesterase 4 inhibitor for the treatment of chronic obstructive pulmonary disease. Br J Pharmacol. 2011;163(1):53-67. doi:10.1111/j.1476-5381.2011.01218.x Comprehensive review of PDE4 biology, roflumilast pharmacology, and the scientific rationale for PDE4 inhibition in COPD.
  2. Essayan DM. Cyclic nucleotide phosphodiesterases. J Allergy Clin Immunol. 2001;108(5):671-680. doi:10.1067/mai.2001.119555 Foundational review of the PDE enzyme family and the role of PDE4 in regulating cAMP-dependent anti-inflammatory pathways in lung tissue.
Pharmacokinetics / Special Populations
  1. Lahu G, Hunnemeyer A, Dilber S, et al. Population pharmacokinetic modelling of roflumilast and roflumilast N-oxide by total phosphodiesterase-4 inhibitory activity and development of a population pharmacodynamic-adverse event model. Clin Pharmacokinet. 2010;49(9):589-606. doi:10.2165/11536600-000000000-00000 Population PK model linking roflumilast and N-oxide exposure to total PDE4 inhibitory activity; supports the concept that both parent and metabolite contribute to clinical effects.
  2. Pinner NA, Hamilton LA, Hughes A. Roflumilast: a phosphodiesterase-4 inhibitor for the treatment of severe chronic obstructive pulmonary disease. Clin Ther. 2012;34(1):56-66. doi:10.1016/j.clinthera.2011.12.008 Clinical review covering pharmacology, drug interactions with quantitative PK data, clinical trial efficacy, and safety profile in COPD.