Editorial illustration of a person pausing exercise to assess knee discomfort while taking isotretinoin

Can I exercise while taking isotretinoin? Muscle and joint pain explained

Amit Goyal

2 minutes ago

5 min read

You can usually stay active while taking isotretinoin, but it is sensible to reduce very intense exercise and pay attention to new muscle, joint or back pain. NHS and UK medicine information warn that vigorous physical activity can make these symptoms more likely or more severe. Most aches are not an emergency, but marked weakness, severe pain, swelling or dark urine needs urgent medical assessment.

This is general information, not a personal exercise plan. Your prescriber’s advice takes priority because the safest level of activity depends on your symptoms, health, training and other medicines.

Why can isotretinoin affect muscles and joints?

Isotretinoin is a prescription-only medicine used for suitable people with severe acne, acne at risk of permanent scarring, or acne that has not responded adequately to appropriate standard treatment. It is not suitable for everyone and should only be started after an individual assessment.

Muscle aches, joint pain and back pain are recognised possible side effects. The British Association of Dermatologists notes that aches can be more noticeable after exercise. UK product information also reports raised creatine phosphokinase, often called CK or CPK, an enzyme that can rise when muscle is stressed or damaged. Vigorous activity is a particular consideration, especially for children and teenagers.

The experience varies. Pain during treatment is not automatically caused by isotretinoin: training, an unrelated injury, infection or another condition may also be responsible.

Do I have to stop exercising completely?

Usually, no. The NHS advises against doing too much intense exercise rather than telling everyone to become inactive. Gentle and moderate activity may remain possible if you feel well, but forcing yourself through worsening symptoms is unwise.

A practical approach is to:

keep your prescriber informed about the type and intensity of exercise you do;
avoid suddenly increasing training volume, weight or intensity;
include rest and recovery days;
reduce or pause the activity that triggers pain;
stay adequately hydrated, particularly during longer sessions or hot weather; and
avoid using painkillers, anti-inflammatory medicines or supplements repeatedly without checking that they are appropriate for you.

There is no single safe mileage, weight or heart-rate limit. Your symptoms and clinical circumstances matter more than an arbitrary rule.

What should I do if I develop aches after exercise?

Stop the session and allow the area to recover. Note where and when pain began, the activity involved, its severity and any weakness, swelling or change in urine colour. This can help your prescriber distinguish ordinary soreness from a medicine-related problem or injury.

Contact your isotretinoin team promptly if pain is persistent, worsening, repeatedly returns with activity or interferes with walking, sleep, work or normal movement. Also seek advice for significant back or buttock pain, marked morning stiffness, a swollen joint or tendon pain. Product information records uncommon inflammatory problems, including sacroiliitis, so persistent symptoms deserve assessment rather than self-diagnosis.

Do not lower the dose, stop isotretinoin or restart it without speaking to the prescriber. They may change activity advice, examine you, review the dose, arrange tests or consider other causes.

When is muscle pain urgent?

Rarely, severe muscle breakdown called rhabdomyolysis can occur. UK patient information warns that this may be associated with intensive physical activity and can damage the kidneys.

Stop exercising and seek urgent medical help if muscle symptoms are accompanied by:

pronounced or rapidly worsening weakness;
difficulty moving an arm or leg;
severe pain, swelling or bruising;
dark brown or cola-coloured urine;
much less urine than usual;
confusion or signs of significant dehydration; or
feeling acutely unwell.

Do not wait for a routine follow-up if these symptoms occur. Use NHS 111 for urgent advice, or 999/A&E if symptoms are severe or you are seriously unwell.

Will I need a CK blood test?

Not everyone taking isotretinoin needs routine CK testing. Standard monitoring more often focuses on liver function and blood fats, with pregnancy testing where relevant. A clinician may consider CK and other tests when there is significant muscle pain, weakness, strenuous training or another clinical reason.

Exercise can raise CK, so results require clinical interpretation. Tell the clinician when you last exercised and what the session involved.

You can read more about the blood tests used during isotretinoin treatment.

What should athletes discuss before treatment?

If sport or physical work is important to you, raise it before isotretinoin starts. Tell the clinician about endurance events, weight training, contact sport, competitions, physically demanding employment and any previous muscle, joint, tendon or back problems. Include all medicines and supplements; “natural” or sports products still matter.

Ask whom to contact between appointments and what symptoms should trigger a review. Safety must take priority over a competition.

Current UK safeguards require isotretinoin to be initiated by a lead prescriber with appropriate expertise in systemic retinoids. The first appointment should be in person; later reviews may be remote when clinically appropriate. Mental health and sexual function must also be assessed and monitored, and the Pregnancy Prevention Programme applies to people who could become pregnant. These requirements are part of a wider safety pathway, not a guarantee that treatment will be prescribed.

Frequently asked questions

Can I go to the gym while taking isotretinoin?

Often, yes, but reduce very intense sessions and stop if you develop concerning pain or weakness. Discuss heavy lifting or high-volume training with your prescriber rather than assuming your usual programme is safe unchanged.

Is normal muscle soreness after a workout dangerous?

Mild, short-lived soreness can have many causes. Seek advice if it is unusually severe, persistent, getting worse or accompanied by weakness, swelling, bruising, dark urine or reduced urine output.

Can I run or play competitive sport?

Some people continue, but the answer depends on intensity, symptoms and individual health. Avoid sudden training increases and agree a plan with your isotretinoin team, especially if you train hard or compete.

Will muscle and joint aches go away?

Many side effects improve after treatment is adjusted or completed, but persistent symptoms should be assessed.

Taking the next step

If acne is severe, scarring or has not improved with appropriate treatment, arrange an acne assessment rather than seeking a predetermined prescription. mySkinDoc offers remote skin consultations for suitable concerns. An online review may help clarify next steps, but isotretinoin requires the current UK assessment and monitoring pathway, including an in-person first appointment, and no particular medicine can be guaranteed.

References

Sources checked 26 October 2026.