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Muscle Spasms Herceptin

Bee Flower
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I’ve had Herceptin/Pertuzumab treatment for secondary breast cancer for 9 years. I’m very fortunate that treatment is working very well for me and I’m able to live an active life. A few years ago, I started having strong muscle spasms. I didn’t mention it as I thought it was not related to my treatment. I have read on Cancer Research website that muscle spasms can happen with Herceptin so I mentioned it to my consultant. While she is excellent and there’s no doubt I would not be here without the wonderful oncology team, she seemed not to have heard of muscle spasms as a side effect. I just wondered if this side effect is unusual? I have been offered Baclofen to try but I’m concerned it might make me drowsy. 

  • Hello Bee Flower,

    Thanks for getting in touch and welcome to our online community.

    It’s good to hear that your treatment has been working well for you. It’s understandable that you are looking to understand more about your muscle spasms.

    Looking at prescribing information for Herceptin it suggests that 3-4% of people experience muscle spasm. Drugs.com list it under less common side effects. This may be why your consultant was not been aware of it, as a side effect.

    I appreciate that this information does not help your experience of muscle spasm. It may be worth trying the baclofen, as you may not experience drowsiness from it. If you are still not keen, I would encourage you to discuss alternatives with your consultant and/or GP.

    You may find it helpful to discuss with a physiotherapist, to see if they can offer non-drug alternatives. Your team should be able to refer you or sometimes this can be done with self-referral. Your GP practice should be able to give you the local contact number.

    I hope this helps.

    We often find we can help more by exploring these questions over the phone. If this is something you think would help, then please don’t hesitate to get in touch via our support line on 0808 808 0000. We are available 7 days a week, 8am-8pm.

    I hope this helps.

      

    Best wishes, 

    Linda J. Cancer Information Nurse Specialist 

     

    You can also speak with the Macmillan Support Line team of experts. Phone free on 0808 808 0000 (7 days a week, 8am-8pm) or send us an email. 

    Ref: LJ/CF

     

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