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Tamoxifen at night or in the morning?

linn56 Member Posts: 11

I'm wondering what people do, in general, and the rationale behind the decision. I started off splitting the pill and taking half in the morning and half at night. I did it like that for maybe 5 weeks. But I was having problems with increasing insomnia for about 2 weeks that I couldn't trace to any cause. I take Rozerem and Neurontin at night for insomnia to begin with (Neurontin to stop restless leg that kept me awake).

I switched the Tamoxifen to morning to try it out, and lo, the insomnia stopped.  Coincidence or cause? My chief side effect on Tamoxifen has been hot flashes, and they have followed the same pattern mine did before starting the drug. I usually don't have them at night, or not badly, so that is not what was keeping me awake.

I have not seen insomnia on any list of side effects. Has anyone else experienced insomnia on it?


  • rebilla
    rebilla Member Posts: 1
    edited April 2010

    hi, i started taking tamoxifen at night,at the beginning of december and within 2 weeks was suffering with dreadful hot flushes and insomnia throughout the night, but fine during the day. when i told my ps she told me to take it in the morning instead,for a month to see how it affected me then. well,my months just about up and i am sleeping considerably better,with less hot flushes and still fine during the day,so i am going to keep on taking it in the other side effects. carol.

  • mawhinney
    mawhinney Member Posts: 14
    edited April 2010

    I'm curious about splitting the pill. Was this on your doctor's rcommendation or did you decided to do this on your own?

  • adrienne2
    adrienne2 Member Posts: 4
    edited April 2010

    I've been taking my Tamoxifen at noon. Hot flashes hit in the evening, and usually one or two right after I go to bed, but that was my pattern before I started taking Tamoxifen. I seem to be sleeping as well as ever. Not well, but as well as I did before.


  • gfbaker
    gfbaker Member Posts: 4
    edited April 2010

    I take my tamox at night with no sleep issues. Of course I am also lucky enough to not have weight gain issues either. And no hot flashes either. Gosh, I hope its working for me!

  • Kleenex
    Kleenex Member Posts: 310
    edited April 2010

    I take mine at bedtime. It actually makes me SLEEPY - no insomnia from it. Although if it's very humid and/or I've eaten a big fabulous fatty meal, I'll be awakened to enjoy lots of hot flashes. I often take 3 mg of Melatonin with it when I take it at bedtime to enhance the sleepiness effect and hopefully sleep through any flashing. I've taken it since 12/1/08.

  • conniehar
    conniehar Member Posts: 585
    edited April 2010

    I have insomnia from the Tamoxifen.  At least that is what I believe it to be from.  I started off taking it at night and switched it to the morning but I still have terrible insomnia.  I have to take a sleeping pill every night.  If I don't I am wide awake the entire night.  It is not on the normal list of side effects but I have heard more than a few people claim insomnia so that's what I am sticking with!  Good luck everyone!

  • kcjules
    kcjules Member Posts: 2
    edited July 2020


    I know this is an old thread but I am starting Tamoxifen 8/2/20 and was wondering the same thing. When did you end up taking it? How was it for you? How are you now?
    Thanks for any insight.

  • bcincolorado
    bcincolorado Member Posts: 4,685
    edited July 2020

    When I took Tamox I had one pill in the morning and one at night Did fine on it that way I was advised to take it that way by my MO to help kevels even.

  • flashlight
    flashlight Member Posts: 311
    edited July 2020

    I take 10mg in the Am and 10mg at bedtime. I still have insomnia on some days or difficulty falling to sleep. With the 10mg dose I no longer have night sweats and just a hot flash now and then. When I went off of Tamoxifen for a hysterectomy I didn't have any problems sleeping. Does anyone have a recommendation on what to take? My primary recommended trazodone, mirtazapine(increases appetite), and amitriptyline. I haven't tried any of these. I take melatonin and costco's sleeping aid, but sometimes it just doesn't work.

  • BlueGirlRedState
    BlueGirlRedState Member Posts: 900
    edited August 2020

    flashlight - no recommendations on what to take for insomnia, but the drugs your primary suggested sound strong, and possibly addictive. I have resisted any suggestion of more drugs. I am not experiencing insomnia now, but have gone through episodes of it and it really sucks. First time, about the time when I became premenopausal. I probably already had undetected BC. Later on with 3 episodes of BC and various teatments, occasional boughts of insomnia. No problem falling asleep, but I would wake up 1 or 2 in AM, wired, restless, monkey braining, unable to sleep. It could go on for weeks. I've tried CBD with/without THC including a tincture that a friend reported great success with, but it did not help me. I tried a various forms of THC, none helped, one was really bad ( very wired and cotton mouth all night). I've heard that tea from hops is helpful, have only found that with beer or "nighttime" teas. Watching sugar, especially late in day helps. Staying active, and staying hydrated helps. I take melatonin and magnesium 1-2 hrs before bedtime, I think it helps me stay asleep. In colder months I drink various nighttime teas chamomile, "Nighty Night", "Pukka", Goldenmilk (turmeric mixture). Acupuncture might help as well.

  • flashlight
    flashlight Member Posts: 311
    edited August 2020

    BlueGirlRedState , Thank you for your comments. I was curious about the CBD/THC, but haven't tried any. Very expensive!! I will try the teas. I try to keep busy. I just finished painting 2-bathrooms for my daughter with a 45 min ride each way and I still couldn't sleep!! About every 3nights I sleep well. At least that is something. Beer? interesting....

  • Blue311
    Blue311 Member Posts: 4
    edited September 2020

    I took tamoxifen at night time and it caused bad dreams and trouble sleeping, i switched to taking the pill earlier in the day and it has really helped with my sleep.

    i take the medication with food, and my sleep has improved. I sometimes have insomnia, but I think its more due to my anxitey.