Affenid XL (methylphenidate)
Methylphenidate hydrochloride (prolonged-release tablet)
Affenid XL is a once-daily methylphenidate tablet for ADHD. It is listed by the NHS as a match for Concerta XL. This guide explains its duration, doses, side effects and changing brands safely.
Also searched for as Afendid, Affendid, Afenid.
Written and clinically reviewed by Adam OdusholaADHD Advanced Practitioner and Clinical Prescribing Pharmacist
Affenid XL: key facts
- What it is
- Affenid XL is a once-daily modified-release tablet containing methylphenidate: a stimulant that keeps dopamine and noradrenaline available longer in the brain areas that regulate focus, motivation, and impulse control.
- How it's released
- Prolonged-release tablet: an outer coat releases part of the dose in the first 1–2 hours, and the rest is released gradually over the following hours. It is bioequivalent to Concerta XL; the exact split between the immediate-release part and the slow-release part is not published.
- Duration
- Up to 12 hours from a single morning dose.
- How to take it
- Swallow whole with water. With or without food. Do not crush, break, chew, or cut the tablet.
- Available strengths
- 18 mg, 27 mg, 36 mg, 54 mg tablets. Maximum daily dose: 54 mg (children); 72 mg (adults).
- Bioequivalence
- Bioequivalent to Concerta XL. It is on the NHS list of equivalent tablets with Atenza XL, Concerta XL, Delmosart, Matoride XL, Xaggitin XL and Xenidate XL. If supplies run short, your prescriber can switch you to another brand on that list at the same dose. Matoride XL is licensed for children and young people only.
What is Affenid XL?
Affenid XL (Zentiva) is a 12-hour methylphenidate tablet that is bioequivalent to Concerta XL and on the same NHS list of equivalent tablets. It must be prescribed and dispensed by brand name.
Affenid XL at a glance
| Fact | Detail |
|---|---|
| Active ingredient | Methylphenidate hydrochlorideSource: Affenid XL SmPC (eMC) |
| Formulation | Prolonged-release tablet (Zentiva)Source: Affenid XL SmPC (eMC) |
| Release pattern | Outer coat in the first 1–2 hours, the rest gradually over the following hours. Bioequivalent to Concerta XL; exact ratio not publishedSource: NHS list of equivalent brands |
| Strengths | 18, 27, 36 and 54 mg tabletsSource: Affenid XL SmPC (eMC) |
| Usual starting dose | 18 mg once each morning, increased in 18 mg steps no faster than weeklySource: Affenid XL SmPC (eMC) |
| Maximum licensed dose | 54 mg a day (children); up to 72 mg a day (adults)Source: Affenid XL SmPC (eMC) |
| How long it lasts | Up to 12 hoursSource: Affenid XL SmPC (eMC) |
| Food | With or without foodSource: Affenid XL SmPC (eMC) |
| How to take it | Swallow whole. Do not crush, break, chew or cutSource: Affenid XL SmPC (eMC) |
| Bioequivalent brands | Atenza XL, Concerta XL, Delmosart, Matoride XL, Xaggitin XL, Xenidate XL (Matoride XL: children and young people only)Source: NHS list of equivalent brands |
| Controlled drug | Schedule 2Source: BNF: methylphenidate hydrochloride |
Medication class
Affenid XL (Zentiva) is a prolonged-release methylphenidate tablet that is bioequivalent to Concerta XL and on the NHS list of equivalent tablets. It delivers approximately 22% of the dose as an initial release in the first 1–2 hours, with the remainder releasing gradually to maintain 12 hours of therapeutic coverage. Affenid XL needs no food. It is not known to interact with acid-reducing medicines such as omeprazole or lansoprazole, or with antacids. Methylphenidate modified-release products must be prescribed and dispensed by brand name (MHRA guidance). Only change brand with your prescriber.
When it's prescribed
Prescribed for ADHD in children aged 6 and over and adults, per NICE NG87. Must be prescribed and dispensed by brand name (MHRA guidance).
Pros of Affenid XL
- 12-hour duration: full working-day coverage from a single morning dose
- No known interaction with acid-reducing medicines such as omeprazole or lansoprazole, or with antacids
- No food requirement
- Bioequivalent to Concerta XL: the reference product
- Part of the largest UK bioequivalence group: supply options available within group
Cons of Affenid XL
- Tablet must be swallowed whole: cannot be crushed, cut, or opened
- The effect builds gradually through the morning rather than peaking early
- You may see an empty tablet shell in your stools; this can be normal, but it does not show how much medicine was absorbed
How does Affenid XL work?
An outer coat releases part of the dose in the first 1–2 hours, and the rest releases gradually over the following hours. The tablet must stay intact for this to work.
Methylphenidate blocks the brain's recycling transporters for dopamine and noradrenaline: keeping them available longer in the synapse. This isn't the same as amphetamines: methylphenidate slows the drain rather than turning up the tap.
Affenid XL is a prolonged-release tablet bioequivalent to Concerta XL (the reference product). It delivers an initial portion of the dose in the first 1–2 hours, then releases the remainder gradually: maintaining therapeutic plasma levels for up to 12 hours.
The tablet must remain intact for the release mechanism to work correctly. Crushing or breaking it releases the full dose at once.
You can take Affenid XL with acid-reducing medicines such as omeprazole or lansoprazole, and with antacids. None of them is known to affect it.
How Affenid XL works: visual guide
Follow the methylphenidate in Affenid XL from tablet to effect. Use ADHDnotepad's animated visual medication journey to see how methylphenidate reaches the brain and slows the reuptake of dopamine and noradrenaline, so they stay active for longer. As a Concerta XL bioequivalent, Affenid XL releases this gradually.
ClinicalDeeper clinical detail
How do I take Affenid XL?
Take your prescribed dose once each morning, before 9am, with or without food. Swallow each tablet whole: do not crush, break, chew or cut it.
Interactive Affenid XL duration & effect chart
See how Affenid XL may work through a full day. Use ADHDnotepad's interactive Affenid XL effect chart to slide the dose time and change strength and explore how a prolonged-release tablet, with part of the dose released early and the rest over the following hours, may kick in, hold and wear off. The chart is illustrative, as actual onset and duration vary between people.
When to take it
Once in the morning. Up to 12 hours' duration: take before 9am to avoid it being active at bedtime.
With or without food
Either is fine: Affenid XL does not require food.
Swallow whole
Take with a full glass of water. Do not crush, break, chew, or cut the tablet: the prolonged-release mechanism only works as an intact tablet.
Tablet shell in stools
You may notice something that looks like a tablet in your stools. This can be normal: the outer shell does not dissolve and leaves the same way food does. Seeing it does not tell you how much medicine was absorbed. If you repeatedly see what looks like an intact tablet, or treatment is not helping, ask your pharmacist or prescriber.
Missed dose
If still morning, take as soon as you remember. If mid-afternoon, skip it and resume tomorrow. Never double up.
Alcohol
Avoid entirely. Alcohol can cause dose-dumping from the prolonged-release mechanism and reacts with methylphenidate to form ethylphenidate. Both carry risk.
Before surgery
Tell your surgical team you take methylphenidate. Check with your prescriber about whether to take it on the day of surgery.
ClinicalPrescribing and clinical detail
What should I expect from Affenid XL week by week?
Appetite dips and mild headaches are common in week 1 and mostly settle by week 2. Your prescriber increases the dose gradually, and most people are settled on their dose within 4–8 weeks.
Adjustment
Appetite dips (especially afternoons); mild headache (drinking enough water may help); possibly feeling more alert or on edge. Most settle by week 2.
Settling in
Most early side effects reduce. Coverage builds gradually: some people notice the effect strengthens through the morning rather than being immediate. This is how prolonged-release tablets work.
Optimising
Titration in 18 mg increments. The goal is the lowest dose that manages symptoms well for long enough, with the fewest side effects.
Maintenance
Reviews every 6 months. BP, HR, and weight checked at each visit.
What are the side effects of Affenid XL?
Reduced appetite, difficulty sleeping if taken late, mild headache and a faster heartbeat are the most common early effects. Most ease in the first few weeks.
All expanded by default: tap a category to collapse it. Most of these ease in the first 1–2 weeks.
Reduced appetite; weight loss (long-term)
Common (reported more often in adults)Weight is monitored at every review.
What helps
- Eat breakfast before or with your dose, before your appetite drops.
- Appetite usually returns in the evening: plan your main meal for then.
- If you can, prepare it earlier in the day, while the medicine is working.
- Balanced ready-to-heat meals (freshly made, not processed microwave meals) save the planning that stops many people eating.
Difficulty sleeping if taken late
Very commonWhat helps
- Take before 9am.
- Cut down on caffeine, especially after midday: it often makes stimulant side effects worse.
- The interactive Affenid XL duration & effect chart shows how a change of timing affects when it wears off.
- Tell your prescriberStill disrupted at 4 weeks: discuss with your prescriber.
Increased heart rate and blood pressure; palpitations
CommonModest increases are expected and monitored at every review.
Brief awareness of your heartbeat is usually normal in the first few weeks.
What helps
- Cut down on caffeine and avoid cold and flu remedies that contain a decongestant.
- Keep salt and alcohol down, and keep up regular moderate exercise.
- Tell your prescriberTell your prescriber within a few days if your resting pulse stays above 100. The same if your blood pressure stays at 140/90 or higher (135/85 at home).
- Get help todayA reading of 180/120 or higher after 5 minutes' rest, or a resting pulse above 120: contact your prescriber or 111 today.
- Tell your prescriberContact your prescriber if it's sustained or comes with dizziness.
Anxiety, irritability, low mood
CommonWhat helps
- Note when it happens: as the dose is kicking in, while it is working, or as it wears off.
- Tell your prescriberTell your prescriber if persistent.
Suicidal thoughts
Uncommon- Get help todayContact prescriber or crisis support immediately.
- Call 999If you feel you might act on these thoughts, or you have harmed yourself, call 999 or go to A&E.
Psychosis symptoms; mania
Uncommon/Rare- Get help todayStop and seek urgent review.
Headache
Very commonUsually settles by week 2.
What helps
- Drink more water.
Dizziness, tremor
Common (dizziness); uncommon (tremor)What helps
- Don't drive while dizzy.
Tics
Common (worsening of existing tics is uncommon)- Tell your prescriberContact your prescriber.
Nausea, dry mouth, sweating
CommonNausea is most common in the first weeks.
What helps
- Taking your dose with or after food may help.
- Drinking enough water and eating regular, smaller meals may help.
- For a dry mouth, sip water and use sugar-free gum or mints.
- Tell your prescriberMention it at your review if it bothers you or is severe.
- Tell your prescriberMention the others at your next review if troublesome.
Priapism (painful erection more than 2 hours)
Frequency not known: medical emergency- Call 999Attend A&E immediately.
This is the full list for this guide, including uncommon and rare effects. For step-by-step tips on managing the common ones, and when to speak to your prescriber, see Affenid XL side effects: what helps.
When should I get help while taking Affenid XL?
Call 999 for severe or spreading chest pain, severe breathlessness, signs of a stroke, a seizure or a suspected overdose. Call 999 too for a severe allergic reaction: sudden swelling of the lips, mouth or throat, or difficulty breathing. Contact your prescriber or 111 today for mild chest pain, a resting heart rate above 120, fainting, hallucinations or thoughts of self-harm (call 999 if you might act on them). Most other early effects can wait for your next review.
Emergency: call 999 or go to A&E
- Severe chest pain, or chest pain spreading to your arm, jaw or back
- Severe shortness of breath or struggling to breathe
- Suspected stroke (FAST)
- Seizures; loss of consciousness; suspected overdose
- Priapism (a painful erection lasting more than 2 hours): go to A&E straight away
- Thoughts of harming yourself or someone else that you feel you might act on, or you have harmed yourself
- Severe allergic reaction (anaphylaxis): sudden swelling of the lips, mouth, throat or tongue, or difficulty breathing or swallowing. Call 999.
Expected: mention at next review
Common in the first few weeks: no action usually needed
- Reduced appetite (stable)
- Mild headache weeks 1–2
- Dry mouth
- Mild sleep difficulty
- Mild irritability improving
Contact your prescriber within a few days
Not urgent: but worth discussing if ongoing
- Resting HR consistently >100 bpm
- BP persistently raised
- Headaches beyond 2 weeks
- Mood changes not settling at 4 weeks
- Sleep severely disrupted beyond 4 weeks
- Significant weight loss
- Tics appearing
- Blurred vision; Raynaud's symptoms
Contact prescriber or 111 today
Do not wait for a routine appointment
- Mild chest pain or chest tightness
- Resting HR >120 bpm; BP significantly raised; fainting
- Suicidal thoughts
- Hallucinations or psychosis
- New mania
- A new rash, without swelling or breathing problems
- Signs of very high blood pressure (severe headache, vision changes, confusion)
What you can safely try while waiting for a review
- Headache: drink more water; avoid caffeine after midday
- Appetite: eat breakfast before your dose; keep nutritious snacks for the evening
- Sleep: take your dose 30 minutes earlier; avoid screens after 10pm
- Anxiety: track whether worse on dose days vs off days: helps your prescriber
- Dry mouth: sugar-free gum; frequent small sips of water
Frequently asked questions about Affenid XL
How is Affenid XL different from Concerta XL?
They have the same clinical profile: Affenid XL is bioequivalent to Concerta XL, and both are on the same NHS list of equivalent tablets. They contain the same active ingredient at the same dose and have the same 12-hour duration. The manufacturers differ (Affenid XL is made by Zentiva; Concerta XL by Janssen-Cilag). Your prescriber or pharmacist may have chosen Affenid XL for availability or formulary reasons.
My pharmacy gave me a different brand. Is that okay?
Not without speaking to your prescriber first. Even though Affenid XL is part of the tablet bioequivalence group, brands should not be swapped without guidance. Ask your pharmacy to order Affenid XL specifically.
Can I take it with omeprazole?
Yes: omeprazole, lansoprazole, other acid-reducing medicines and antacids are not known to affect Affenid XL. (This is different from Medikinet XL, where they are contraindicated.)
Can I drink alcohol?
Avoid it entirely: dose-dumping risk and ethylphenidate formation.
There's a shell in my stools. Has the tablet passed through without working?
Not necessarily. An empty tablet shell can pass in your stools because the outer shell does not dissolve. This can be normal with Affenid XL. Seeing it does not tell you whether the treatment gave enough benefit or prove how much medicine was absorbed. If you repeatedly see what looks like an intact tablet, or treatment is not helping, ask your pharmacist or prescriber.
I'm pregnant or breastfeeding: what do I need to know?
Pregnancy: Speak to your prescriber before changing anything, and do not stop without advice. The current evidence is summarised in the BUMPS leaflet on methylphenidate in pregnancy.
Breastfeeding: Methylphenidate is considered the stimulant of choice during breastfeeding (Breastfeeding Network). Milk levels are very low. You do not need to stop breastfeeding. Use the lowest effective dose, time doses after feeds where possible, and monitor your baby.
What should I ask my prescriber about Affenid XL?
Questions worth raising at your next review. You don't need to cover all of them: pick the ones that feel most relevant.
- Why Affenid XL for me specifically?
- What dose are we starting at, and what is the maximum?
- What if my pharmacy can't get Affenid XL: can they give me a different brand?
- What side effects should I call you about?
- I take [list medications]: are any of these a concern?
- If Affenid XL doesn't work well enough, what would we try next?
Affenid XL: notes for GPs and clinicians
Clinical notes by Adam Odushola, ADHD Advanced Practitioner and Clinical Prescribing Pharmacist.
ClinicalBrand and mechanism
ClinicalStrengths, Dosing and Immediate Release Conversion
18, 27, 36 and 54 mg. Start 18 mg once daily in patients new to methylphenidate; adjust in 18 mg steps at approximately weekly intervals (27 mg allows an in-between step). Maximum 54 mg/day in children and 72 mg/day in adults (SmPC).
Switching from immediate-release methylphenidate
| Immediate-release dose | Total daily dose | Affenid XL once each morning |
|---|---|---|
| 5 mg three times a day | 15 mg | 18 mg |
| 10 mg three times a day | 30 mg | 36 mg |
| 15 mg three times a day | 45 mg | 54 mg |
| 20 mg three times a day | 60 mg | 72 mg (adults only) |
Doses from the SmPC (Table 1), for patients taking IR three times a day at 15 to 60 mg a day.
ClinicalBioequivalence group (SPS August 2025)
Affenid XL, Atenza XL, Concerta XL, Delmosart, Matoride XL, Xaggitin XL, Xenidate XL: interchangeable within group at same dose and quantity if supply disruption. Switches to/from capsule group (Ritalin XL, Medikinet XL, Meflynate XL etc.) or Equasym XL require specialist review. Matoride XL SmPC: licensed for children aged 6 and over; adult initiation is not appropriate (continuation from adolescence only). See the SPS list of equivalent MR tablets.
ClinicalAdult licensing and monitoring
ClinicalKey interactions
MAOIs (contraindicated, 14-day washout); alcohol (ethylphenidate formation, dose-dumping); antihypertensives (reduced efficacy); coumarin anticoagulants (monitor INR).
ClinicalPregnancy and breastfeeding
Pregnancy (BUMPS/UKTIS January 2023): Individual risk-benefit; do not advise abrupt discontinuation.
Breastfeeding (BfN April 2025): Stimulant of choice; very low RID; no need to stop breastfeeding.
This guide is written for educational purposes and does not constitute medical advice. Always follow the guidance of your prescriber or pharmacist. If you have concerns about your medication, contact your clinical team.
Sources
- NICE guideline NG87: Attention deficit hyperactivity disorder: diagnosis and management. NICE
- Methylphenidate hydrochloride (BNF drug monograph). BNF, NICE
- Affenid XL 18 mg prolonged-release tablets: Summary of Product Characteristics (SmPC). electronic medicines compendium (eMC)
- Prescribing and switching between modified-release methylphenidate. Specialist Pharmacy Service (SPS)
- Use of methylphenidate in pregnancy (patient leaflet). BUMPS / UK Teratology Information Service
- ADHD and breastfeeding (factsheet). The Breastfeeding Network
About this guide
- Written and clinically reviewed by
- Adam OdusholaADHD Advanced Practitioner and Clinical Prescribing Pharmacist
- First published
- Last updated
- Last reviewed
- Next review
- What changed
- October 2026: noted that Matoride XL, one of the bioequivalent tablets, is licensed for children and young people only. Also clearer advice on when to call 999 (severe or spreading chest pain, severe breathlessness, or thoughts of self-harm you might act on) and when to get help the same day. Side effect frequencies now use the categories in the product information (SmPC). The headache advice now says drinking enough water may help, instead of naming dehydration as the cause. Signs of very high blood pressure (severe headache, vision changes, confusion) added to the same-day list. The Cons no longer compare the first peak with capsule brands. How it is released no longer states a percentage split: the exact split is not published, and it is bioequivalent to Concerta XL. 21 October 2026: seeing the empty tablet shell is no longer described as proof that the medicine worked or was absorbed.
“Last updated” is when the content last changed. “Last reviewed” is when it was last checked against current sources.
How this content is written, sourced and checked: editorial policy
Spotted an error? Report it by email. This is for website feedback only. It can’t give advice about your own treatment.
Changing from Affenid XL? Check the dose conversion
See how your dose lines up with immediate-release methylphenidate or another brand, and how the day’s doses would be spaced. It is a guide for the conversation with your prescriber, not a prescription.
15 mg a day of immediate-release methylphenidate, for example 5 mg three times a day
Affenid XL 18 mg is listed against a total of 15 mg a day of immediate-release methylphenidate, taken three times a day, in the manufacturer’s conversion table. Each immediate-release dose lasts about 3 to 5 hours, so the day’s cover changes.
- Immediate-release doses are spaced through the day; the last one is usually taken by mid-afternoon to protect sleep.
- This is a guide for the conversation with your prescriber, not a prescription. Your prescriber sets the dose, the start date and the review.
Doses from each product’s manufacturer conversion table and the NHS list of equivalent brands. Read more about switching methylphenidate brands safely.