Arava (Leflunomide) 2025 Guide: Uses, Dosage, Side Effects, Monitoring, and Safety

TL;DR

• Arava (generic: leflunomide) is a once-daily disease‑modifying drug for rheumatoid and psoriatic arthritis. It lowers inflammation and slows joint damage, but it takes 4-12 weeks to kick in.
• Typical dose: 10-20 mg daily. Many skip the 3‑day loading dose to avoid stomach upset. You’ll need regular blood tests for liver, blood counts, and blood pressure checks.
• Common side effects: diarrhea, nausea, hair thinning, rash, higher blood pressure, abnormal liver tests. Serious but rare: severe liver injury, low blood cells, lung issues, severe skin reactions.
• Pregnancy is a hard no. Use reliable contraception. If pregnancy is planned or happens by accident, a “washout” with cholestyramine or activated charcoal is needed.
• Watch interactions: methotrexate (higher liver risk), warfarin (INR can spike), live vaccines (avoid). Keep up-to-date with non-live vaccines like flu, COVID‑19, and pneumococcal.

If your doctor mentioned Arava, you’re probably weighing relief against risk. This is the plain-English, no-nonsense guide I wish every patient got on day one: what it does, what to expect week by week, how to stay safe, and when to call for help. I’m writing from New Zealand, so I’ll flag local notes where it matters, but the safety basics apply anywhere.

What Arava Is and Who It Helps

Arava is the brand name for leflunomide, a disease-modifying antirheumatic drug (DMARD). It works by dialing down immune pathways that drive joint inflammation and damage. If your arthritis is chewing through your energy or you’re waking up stiff and sore, this is one of the workhorse medicines that can change the trajectory instead of just numbing pain.

Who it’s usually prescribed for:

• Rheumatoid arthritis (RA) in adults: to reduce swelling, pain, and long-term joint damage.
• Psoriatic arthritis (PsA): especially when peripheral joints are inflamed.

Where it fits in the treatment ladder:

• Common first-line in patients who can’t take methotrexate (MTX), or as an alternative when MTX causes side effects.
• Used alone or with other conventional DMARDs like sulfasalazine and hydroxychloroquine.
• If arthritis stays active after a fair trial (usually 3 months at the right dose), your team may add a biologic or JAK inhibitor.

How fast it works: don’t judge it too early. Most people feel a difference between weeks 4 and 12. Some feel steadier by month 3 to 4, especially when inflammation markers settle. If you need rapid relief while waiting, your doctor may use a short steroid bridge.

Evidence snapshot (so you know this isn’t just wishful thinking):

• Large randomized trials have shown leflunomide improves tender and swollen joint counts and function in RA, similar to methotrexate for many people.
• Guidelines from the American College of Rheumatology (2021, updates since) and EULAR (2023 update) include leflunomide as a recommended conventional DMARD for RA.
• Medsafe NZ’s data sheet lists it as approved for RA and PsA with clear safety requirements.

How to Take Arava Safely: Dosing, Monitoring, and What to Expect

The goal is to get benefit without tripping on preventable side effects. Here’s the practical playbook.

Dosing basics:

• Standard maintenance: 20 mg once daily. Some start at 10 mg if small body size, older age, or sensitive stomach/liver issues.
• Optional loading dose: 100 mg daily for 3 days. Many rheumatologists skip this to avoid diarrhea and nausea. You won’t miss out long-term; it just speeds up early levels.
• Take with or without food. If your stomach grumbles, take it with dinner.

Time course and milestones:

1. Weeks 0-2: set up baseline labs and blood pressure; discuss vaccinations and contraception; decide if loading dose makes sense.
2. Weeks 2-6: watch gut symptoms and blood pressure. Early labs ensure your liver and blood counts are steady.
3. Weeks 6-12: look for less morning stiffness and swelling. Your dose may be adjusted.
4. Month 3+: reassess for response. If still very active, plan an add-on or switch.

Lab monitoring (the part that keeps you safe):

• Baseline before starting: full blood count (FBC), ALT/AST (liver), creatinine/eGFR (kidneys), blood pressure, weight. Also pregnancy test if you could become pregnant. Screen hepatitis B/C and check vaccination status; TB testing may be done based on risk.
• After starting or changing dose: check FBC and liver enzymes every 2 weeks for 6 weeks, then monthly for 3 months.
• Long-term when stable: every 8-12 weeks (your clinician may space it differently depending on your history).

Red lines that trigger action:

• ALT/AST persistently >2× upper limit: consider dose reduction and recheck.
• ALT/AST >3× upper limit or symptomatic hepatitis (nausea, jaundice, dark urine): stop and start a washout (see below) and arrange urgent review.
• White blood cells or platelets dropping below safe ranges: pause and discuss next steps.

Alcohol: keep it modest. Many clinicians advise no more than 1 standard drink a day and alcohol-free days each week. If your liver tests wobble, skip alcohol.

Vaccines: avoid live vaccines (MMR, varicella, live zoster). Non-live shots-flu, COVID‑19, pneumococcal, and recombinant shingles-are fine and recommended. In New Zealand, talk to your GP or rheumatology nurse about timing if a booster is due.

Contraception and pregnancy planning:

• Teratogenic risk is real. Use reliable contraception during treatment.
• If pregnancy is planned or happens, do a drug “washout” with cholestyramine 8 g three times daily for 11 days (or activated charcoal 50 g every 12 hours for 11 days). Your team may check blood levels of the active metabolite twice at least 14 days apart to confirm it’s low enough before trying to conceive.
• Men matter too: men planning to father a child should discuss a washout as leflunomide’s active metabolite hangs around. Decisions vary by specialist; bring it up early.

Day-to-day tips that make a difference:

• Set phone reminders for your tablet and lab tests.
• Note your blood pressure at home if you have a cuff; write down readings weekly for the first month.
• Keep a simple symptom diary: morning stiffness minutes, worst joint score out of 10, any side effects. It helps at reviews.

Side Effects, Risks, and What to Do If They Happen

Most people can stay on Arava with the right dose and checks. Knowing what to expect-and when to act-keeps bumps small.

Common, usually manageable:

• Diarrhea, stomach upset: try taking with food; split dose to morning and evening if your prescriber agrees; add simple anti-diarrheals short term. If it’s relentless or dehydrating, call.
• Hair thinning: often mild and stabilizes. Good nutrition, biotin if you like (evidence is mixed), and gentle hair care help. This is reversible if the drug is reduced or stopped.
• Rash or itch: mild cases can settle with antihistamines. Any blistering rash or skin peeling-treat as urgent.
• High blood pressure: may need adjustment of your BP meds, diet tweaks, and less salt.

Less common but important:

• Liver inflammation: may show only in blood tests at first. Symptoms include nausea, right‑sided tummy pain, dark urine, jaundice. If any of those show up, stop and seek urgent care.
• Low blood cells (infection or bruising risk): fever, sore throat, mouth ulcers, unusual bruises-call for blood tests right away.
• Peripheral neuropathy: numbness, tingling, or burning in hands/feet. Report early; dose change may stop it progressing.
• Lung issues: new cough or breathlessness that doesn’t track with a cold-get checked. Rare interstitial lung disease has been reported.
• Severe skin reactions (rare but dangerous): Stevens-Johnson syndrome or toxic epidermal necrolysis-painful rash, blisters, peeling skin, fever. Emergency.

Interactions to keep on your radar:

• Methotrexate: sometimes used together under specialist care, but liver risk rises. Monitoring must be tight.
• Warfarin: INR can climb. If you’re on warfarin, you need close INR checks when starting or changing dose.
• Rifampicin: can raise leflunomide levels.
• Leflunomide affects liver enzymes (notably CYP2C8 and CYP1A2). Drugs like repaglinide or some antidepressants may need attention. Always tell pharmacists you’re on leflunomide.
• Cholestyramine or activated charcoal: these bind the drug and are used for washout; they’ll also lower effectiveness if taken routinely.

What to do if you need to stop quickly: the washout

• Because the active metabolite hangs around (think weeks to months), a washout strips it faster.
• Standard washout: cholestyramine 8 g three times daily for 11 days, or activated charcoal 50 g every 12 hours for 11 days.
• After serious side effects or before pregnancy, clinicians often confirm low blood levels on two tests at least 14 days apart.

When to pause Arava:

• Fever or a significant infection needing antibiotics: most clinicians hold until you’re improving.
• Before major surgery: because leflunomide lingers, short pauses may not change much. Your surgeon and rheumatologist may plan a washout for high-risk cases. Ask early.

Who should be extra cautious or avoid it:

• Active liver disease or ALT/AST already elevated.
• Severe immunodeficiency or serious uncontrolled infections.
• Pregnant or planning pregnancy without a washout; breastfeeding.
• Heavy alcohol use.

Credible sources behind the safety rules: Medsafe NZ Arava data sheet (latest updates referenced by clinicians in 2024), ACR RA guideline (2021 with updates), EULAR RA recommendations (2023 update), and independent pharmacovigilance reports. If you like to read originals, ask your clinic for the data sheet and guideline extracts.

Comparisons, Practical Choices, Checklists, and FAQ

Arava isn’t the only DMARD in town. If you’re choosing between options-or wondering what’s next if it doesn’t land-this section helps map it out.

Quick comparison of common DMARD choices:

Decision cues you can use:

• If methotrexate made you miserable, Arava is a reasonable swap that often works similarly.
• If you’re planning a pregnancy soon, choose something else now and keep Arava in your back pocket for later.
• If your liver tests ride high on even small alcohol, be conservative and discuss alternatives first.
• If convenience matters, once-daily dosing is a win compared with multiple sulfasalazine tablets.

Execution checklist (print or save this):

• Before starting: FBC, ALT/AST, creatinine/eGFR, BP, pregnancy test if relevant, hepatitis B/C screen, vaccine check.
• Agree on a monitoring schedule: every 2 weeks (×6 weeks), monthly (×3 months), then every 8-12 weeks.
• Set contraception and pregnancy plan; understand washout steps.
• Know your stop signals: fever on treatment, yellow eyes/skin, dark urine, severe rash, mouth ulcers, unexpected bruising.
• Record your week‑by‑week response and side effects; bring to reviews.

Scenarios and trade-offs:

• Strong response + mild diarrhea: stick with it and tweak timing/food; symptoms often settle by month 2.
• No response at 12 weeks at 20 mg: confirm adherence and labs; consider adding another DMARD or moving to a biologic/JAK per guideline pathways.
• Great response + ALT rises to 2× upper limit: pause alcohol, recheck in 1-2 weeks; consider dose reduction. If it climbs, stop and wash out.
• Planning major surgery: flag early; your team may time a washout depending on infection risk and disease activity.

Mini‑FAQ

Can I take Arava with methotrexate?
Sometimes, under specialist care. It can boost control but raises liver risk, so labs must be tight, and folic acid stays in place for methotrexate side effects.

How long will I be on Arava?
If it works and you tolerate it, often years. The plan is to keep disease quiet and prevent damage. Your team may taper only after a long, stable remission.

Is it safe with colds or COVID‑19?
For mild infections, many continue. If feverish or on antibiotics, most clinicians advise pausing until you’re better. Keep vaccinations up to date.

What about breastfeeding?
Not recommended. Discuss safer alternatives if you’re postpartum and nursing.

Is it funded in New Zealand?
Availability is stable; funding settings can change. Check the current Pharmac schedule and talk to your prescriber about costs and any Special Authority requirements.

Will it affect surgery healing?
Immunosuppression can slightly raise infection risk. For high‑risk procedures, your team may plan a washout. For minor procedures, many continue; always coordinate with both teams.

What if I miss a dose?
Take it when you remember the same day. If it’s the next day, skip the missed one-don’t double up.

Next steps and troubleshooting by persona

• If you’re newly diagnosed and nervous: start at 10 mg without a loading dose, set lab reminders, and schedule a 6‑week check to review symptoms and labs.
• If methotrexate failed you: aim for 20 mg if you can tolerate it, keep alcohol low, and re‑assess at 12 weeks for add‑on or switch.
• If you have borderline liver tests: choose the lower starting dose, skip alcohol, recheck labs more often (every 1-2 weeks first month).
• If pregnancy is on the horizon: pause starting Arava and talk through alternatives; if you’re already on it, plan a washout and confirm low levels before trying.
• If infections keep biting: check white cells, teeth/gums, and skin; update vaccines; consider dose change or an alternative DMARD.

One last practical note from clinic reality: communication beats guesswork. If something feels off-gut, mood, energy, or a rash-don’t wait for the next appointment. A quick message to your GP or rheumatology nurse can save you weeks of discomfort.

Professional references consulted in writing this guide include the Medsafe NZ Arava (leflunomide) data sheet, the American College of Rheumatology RA guideline, and EULAR’s 2023 RA update. Your own prescriber’s advice always comes first, because they know your full picture.