Muscle stiffness from medication (rigidity)
Muscle rigidity is stiffness or tightness in the muscles that makes it harder to move freely. Some antipsychotic medications, and less often other medicines, can cause it as a movement side effect. People notice stiff arms, legs, neck or shoulders, or find that everyday movements take more effort. It is worth raising with your doctor.
Last updated Published by MANOAI Pty LtdDeveloped by clinicians working in psychiatry
Definition
- Muscle rigidity
- Increased stiffness in the muscles that resists movement, felt by the person and often noticed by a doctor when moving a limb.
- In plain words
- Muscles that feel stiff and tight, making movement harder work.
On this page
- What does muscle stiffness from medication feel like?
- Why can antipsychotics cause muscle stiffness?
- Could my stiffness be caused by something else?
- How do I describe muscle stiffness to my doctor?
- Should I stop my medication if I notice muscle stiffness?
- How to keep track of muscle stiffness with EPSpeak
What does muscle stiffness from medication feel like?
Muscle rigidity often builds up slowly, so it can take a while to notice. People commonly describe:
- A stiff neck or shoulders that do not loosen up
- Arms and legs that feel tight or heavy
- Getting out of a chair or turning over in bed taking more effort
- Arms that no longer swing much when walking
- A face that feels less expressive, or that others say looks fixed
- Aching muscles that feel tense all the time
Some people simply say their muscles feel stiff from their meds. A doctor examining the arm may feel a stiffness that gives way in small jerks, sometimes called cogwheel rigidity.
Why can antipsychotics cause muscle stiffness?
Antipsychotic medications that block dopamine reduce signalling in the brain pathways that keep movement smooth and relaxed. That can leave muscles feeling tighter than usual. Stiffness is one part of drug-induced parkinsonism, a pattern of side effects that can also include tremor and slowed movement.
It usually develops over weeks to months after starting a medicine or increasing the dose. How likely it is depends on the individual medicine, the dose and the person.
Could my stiffness be caused by something else?
Yes. Muscle stiffness is very common and has many possible causes, including exercise, injury, poor sleep, stress and tension, arthritis and other health conditions. Only a doctor can say whether a medicine is involved.
It helps to notice whether the stiffness is new, whether it affects both sides of the body, and whether it began around the time a medicine was started or changed.
How do I describe muscle stiffness to my doctor?
Try to cover:
- When the stiffness started, and any medication or dose change around then
- Which muscles feel stiff, and whether it is worse on one side
- Whether it is there all day or worse at certain times
- Everyday tasks that have become harder, such as dressing, turning your head or getting up
- Whether anyone has noticed you moving differently
Should I stop my medication if I notice muscle stiffness?
No. Do not stop or change a medication on your own, even if you think it is causing muscle stiffness. Stopping suddenly can bring back the symptoms the medicine was prescribed for, or cause other effects. Contact your doctor or care team, tell them what you have noticed, and decide on next steps together. Movement side effects are well recognised, and there are usually options to talk through.
How to keep track of muscle stiffness with EPSpeak
EPSpeak lets you log your medications and doses alongside a short daily check-in and notes on how your body feels. Because stiffness can creep up slowly, a record over weeks makes gradual change much easier to see than day-to-day memory.
EPSpeak does not diagnose muscle rigidity and cannot tell you what is causing it. You can share your record with a clinician you choose using a QR code.
When to get help straight away
Call 000 or go to an emergency department if you notice:
- Sudden, severe muscle stiffness together with a high temperature, heavy sweating, confusion or a racing heartbeat. This can be a rare but serious reaction to some medicines and needs urgent care.
- Muscle spasms that twist the neck, pull the eyes upwards or lock the jaw, or any difficulty breathing or swallowing.
Other movement side effects
- Shaky hands, trembling (Tremor)A shakiness you can see or feel, often in the hands. It may be easier to notice when you are holding something still, like a cup or a phone.
- Can't sit still, restless inside (Akathisia)A restlessness that feels like it comes from the inside, and an urge to keep moving. Some people describe it as being unable to settle, even when they are tired.
- Slowed down, moving heavily (Bradykinesia)Movements that feel slower or heavier than usual. Things you normally do without thinking, like buttoning a shirt or walking to the door, may take longer.
Common questions
Usually not. Muscle stiffness caused by a medicine often eases after a doctor adjusts the medicine, the dose or the plan around it, although how quickly differs between people. Do not stop or change your medicine yourself to find out. Record when the stiffness started and how it affects you, and talk it through with your doctor.
Cogwheel rigidity is a type of muscle stiffness a doctor may feel when they gently bend and straighten your arm: instead of moving smoothly, it gives way in small jerks, like a ratchet. It is one sign doctors look for in drug-induced parkinsonism and in Parkinson's disease. It is found on examination, so describe your stiffness and let your doctor check.
Muscle rigidity is much more often linked to antipsychotic medications than to antidepressants. Stiffness has many everyday causes, such as tension, exercise or poor sleep, so it may not be related to your medicine at all. If you notice new stiffness after starting or changing any medicine, write down when it began and mention it to your doctor.
Keep a clear record with EPSpeak
Log your medications, check in each day in under a minute, and share your record with your clinician when you choose. Free on Android and iPhone, with no account needed.
Sources
Side effect information on this site draws on published comparative research. Medicines are described by class only.
- Huhn M, Nikolakopoulou A, Schneider-Thoma J, et al. Comparative efficacy and tolerability of 32 oral antipsychotics for the acute treatment of adults with multi-episode schizophrenia: a systematic review and network meta-analysis. The Lancet. 2019.
- Leucht S, Cipriani A, Spineli L, et al. Comparative efficacy and tolerability of 15 antipsychotic drugs in schizophrenia: a multiple-treatments meta-analysis. The Lancet. 2013.
- Taylor DM, Barnes TRE, Young AH. The Maudsley Prescribing Guidelines in Psychiatry, 14th edition. Wiley Blackwell. 2021.