I agree with Beaverntx, the side effects seem to come and go. The first several months the joint pain was really bad but that eased off. However, the hair falling out, plugging the shower, clogging the dryer lint trap, all over the floor, IN OUR FOOD! Lord! I warn people before they eat here, you're probably going to find a hair in your lasagna. I have not yet resorted to wearing a hair net in the kitchen, but it's close!

I'm post menopausal and on Tamoxifen (end of 4th month) plus had a hysterectomy/ovary removal and have yet to have a hot flash. Menopause was easy and I've never had hot flashes so hope I don't get them. I'm also cold a lot even in warm temperatures. Weird. I'm having enough problems with stomach pain and lack of sleep.

edj3 I was post menopausal when I started tamox, had a very easy menopause in physical terms, no hot flashes. But I did have insomnia, anxiety and depression about the same time, took antidepressants for a couple of years, then was fine again. Then when I started tamoxifen, within a couple of weeks I was a complete wreck emotionally, couldn't sleep, couldn't stop crying, sometimes couldn't put one foot in front of the other. So now I take mirtazapine, which has put me back on an even keel. To be honest, I don't even know that the tamoxifen was to blame, it wasn't exactly a great time in my life right then. Apart from that, I've never had any side effects from the tamoxifen that I know of.

I was looking up some stuff about being a poor metabolizer of CYP2D6. I don't know for sure whether I'm a poor metabolizer but I did read that that is the same pathway for metabolizing codeine and opiates. And a few years ago I was told I don't metabolize codeine. It just doesn't work on me, no painkilling effect, no sleepiness, no nausea. And the Oramorph I had after surgery had no effect either. So I wonder if being a poor metabolizer of opiates is a marker for being a poor metabolizer of tamoxifen? In which case, it's probably doing me no damn good anyway.

Ugh so much to have to think about--thank you all for sharing.

Salamandra, I saw you wrote about Provigil. Inwas extremely fatiqued when I started Tamoxifen, but at the time I thought it was a combination of finishing up radiation and starting Tamoxifen. The fatigue did not stop so I finally said something to my oncologist. She sent me to the psych/oncology md and she put me on Provigil. It made a big difference. I ended up having neurological testing and she switched me over to Concerta which I take Monday through Friday. I was very resistant to taking medication but i am glad I changed my mind. Now i am even trying accupuncture for hot flashes! Good luck

DizzyBee - does your MO know about the fact you shared re: Codiene/pain killer drugs not metabolizing for you? If not, I would tell them. That would worry me. Yes, there isn't conclusive evidence in the medical community about the effectiveness/benefit of offering the CYP2D6 enzyme pathway test as of yet, BUT IMO I had been told that I am a KNOWN NON-METABOLIZER of a drug that uses it, well I would ask for that dang test at the very least. We already are rolling the dice whether Tamoxifen works for us, that's despite any info on the pathway. I'd hate for you to suffer any SEs of Tamoxifen and not even have the chance of having any benefit at all because your body doesn't even turn it into the medicine our bodies convert it to in order to block the estrogen. Keep us posted.

Rah2464 - Sounds like you have a very proactive MO. Awesome. Can I ask, how did you get the testing approved or did your MO suggest it or did you bring it up to them? My MO wouldn't do more than listen to me about the test and then say because there's no studies or guidelines on it, it's a test in her opinion that doesn't offer any benefits. That's about the only place that her and I have disagreed on so far.

Lewhy & Salamandra - Thanks for sharing the info about Provigil and Concerta. It's always good to have more tools in the toolbox to fight fatigue if needed. So glad to hear they are working for you both on that SE front! Hope it stays that way!

Here are some helpful links and info on CYP2D6 as in regards to Tamoxifen. HOpefully this is helpful to someone.

Rosabella - To my knowledge, any doctor can order this testing. There are many labs that offer it on their websites, like LabCorp and GeneleX.

Introduction to CYP2D6 and CYP2D6 testing

"Pharmacogenetic testing and the use of testing in clinical practice is a relatively new, evolving and complex topic. This short summary provides an introduction to the basic concepts that need to be considered in relation to cytochrome P450 2D6 (CYP2D6) and CYP2D6 testing.

Enzymes, genes and pharmacogenetics

Differences in the response of individuals to the same drug at the same dose may occur as a result of interindividual differences in enzymes (e.g. CYP2D6) responsible for metabolising the drug. These differences may be inherited and occur as a result of differences in the genes (e.g. CYP2D6) that encode the enzyme."

Study Suggests Earlier Research on CYP2D6 Is Flawed (From BCO.org)

"A new study by researchers at the Mayo Clinic suggests that the large studies on CYP2D6 may be flawed because the studies did the genetic testing on samples of tissue from the breast cancer rather than on healthy tissue.

The study is published in The Journal of the National Cancer Institute, vol. 107, issue 2. Read the abstract of "Loss of Heterozygosity at the CYP2D6 Locus in Breast Cancer: Implications for Germline Pharmacogenetic Studies.""

"Still, when the researchers compared CYP2D6 genotypes that came from breast cancer tissue to CYP2D6 genotypes that came from healthy tissue, they found that about 20% of the genotypes were misclassified.

"The potential benefit of CYP2D6 testing is obvious, but has been difficult to establish," said Matthew Goetz, M.D., a Mayo Clinic oncologist and senior author of the study. "We found that if you use tumor tissue to determine the CYP2D6 genotype a patient was born with, you are going to get it wrong a substantial portion of the time.""

"Editor's Note: In 2018, the Clinical Pharmacogenetics Implementation Consortium, an international group of scientists that issues guidelines on the effects of genetic factors on reactions to drugs, issued a guideline on using CYP2D6 genotype information to make decisions about prescribing tamoxifen after surgery to treat hormone-receptor-positive breast cancer. The guideline strongly recommends that people with an abnormal CYP2D6 genotype that makes them less able to metabolize tamoxifen be treated with a different type of hormonal therapy, such as an aromatase inhibitor."

Labratory Testing of CYP2D6

"Currently, in both premenopausal and postmenopausal patients with invasive breast cancer involving estrogen receptor–positive tumors, long-term therapy with tamoxifen is the standard treatment.16 This treatment reduces the recurrence risk by ~50%.17 The clinical outcome of interest is recurrence of cancer, but an intermediate end point could be endoxifen levels. Several studies have shown that circulating levels of endoxifen are lower in the presence of fewer functional CYP2D6alleles.4,18 If lower endoxifen levels are associated with reduced effectiveness of tamoxifen therapy, CYP2D6 genotyping may provide useful information in personalizing cancer treatments. It has been suggested that patients with no functional CYP2D6 alleles should be offered alternatives to tamoxifen.19"

Tamoxifen Therapy and CYP2D6 Genotype

"At this time, the FDA-approved drug label for tamoxifen does not discuss genetic testing for CYP2D6 (Table 1) (1). The National Comprehensive Cancer Network (NCCN) Breast Cancer Panel does not recommend CYP2D6 testing as a tool to determine the optimal adjuvant endocrine strategy (Table 2), and this recommendation is consistent with the 2010 update of the American Society of Clinical Oncology (ASCO) Guidelines (the most recent update, 2014, does not discuss pharmacogenetic testing) (2, 3).

The Clinical Pharmacogenetics Implementation Consortium (CPIC) recently published updated guidelines for the dosing of tamoxifen based on CYP2D6 phenotype, with therapeutic recommendations for each metabolizer phenotype (Table 3). For CYP2D6 poor metabolizers, CPIC recommends using an alternative hormonal therapy, such as an aromatase inhibitor for postmenopausal women; or an aromatase inhibitor along with ovarian function suppression in premenopausal women. This recommendation is based on these approaches being superior to tamoxifen regardless of CYP2D6 genotype, and the knowledge that CYP2D6 poor metabolizers who switched from tamoxifen to anastrozole do not have an increased risk of recurrence. The CPIC recommendation also states that higher dose tamoxifen (40 mg/day) can be considered if there are contraindications to aromatase inhibitor therapy; however, the increased endoxifen concentration among CYP2D6 poor metabolizers treated with a higher tamoxifen dose does not typically reach the level as in normal metabolizers (4).

Recommendations from the Dutch Pharmacogenetics Working Group (DWPG) of the Royal Dutch Association for the Advancement of Pharmacy (KNMP) also discuss using an alternative drug to tamoxifen in CYP2D6 poor metabolizers (Table 4) (5)."

I lost weight initially, but I think it was left over stress. Now I'm getting thicker and thicker. Hate it.

Hi anxious 789, I have been doing weight watchers and am averaging a one pound per week weight loss on Tamoxifen. It will be 20 weeks, Wednesday, and I am hoping to hit 20 pounds gone! My MO was surprised to hear I am losing on Tamoxifen and I was not really sure how to take that, but anyway, I am losing! Maybe give WW a try?

If anyone can shed light on this I am all ears.

It is known that a small percentage of women do not metabolize tamoxifen. That it does them very little good. They would be more protected taking a different medication for hormone positive breat cancer.

In some of the reading I've done, and I admit a lot of those wordy, technical studies fly right over my head, I found more than one mention that in women who are poor metabolizers, 40mg a day may help the situation, instead of the regular 20mg a day.

Here's what I don't understand. If you are a poor metabolizer at 20 mg, where is the mechanism by which MORE of it will be metabolized? Like, if you do not understand German and you are confused listening to one German speaker, by having three of them talk at you at the same time you will suddenly start understanding German? I do not understand how MORE of something that you don't metabolize will suddenly FORCE you to metabolize?

I am not saying that this is not happening and not possible. I just want to understand the HOW, and so far I do not get it.

Runor and Lewhy, thank you for the reply. I am just being paranoid on losing weight with less effort.

I read that one of the side effect of Tamoxifen is swelling - does anybody here have swelling around the eye and eyebrow? My Opthalmologist think there is nothing to worry about but these doctors seems to down play everything. Any input will be much appreciated

Anxious789. Swelling. Get coffee or wine. Long boring post coming.

I had one lousy lymph node removed and ended up with lymphedema all over the place. My breast, armpit, shoulder blade, ribs, side and arm swelled. Still do. Some bras make the swelling worse. Some days it's better, other days worse. But when it was really bad, back nearer the surgeries, I swear my throat and one side of my face swelled too. It was subtle. I looked more double chinny than normal. And I felt it. It didn't feel like fat, it felt like something that had shown up and was not normally there.

Surgeries and radiation are a shock to the system, lymph system especially if surgery has been done to dig out a few nodes. I think the effects of this are grossly downplayed.

I looked up videos on lymph drainage massage and came across a lady doing facial lymph drainage massage and I thought, well here's a cuckoo bird making some crazy, half baked Youtube tutorial. She was rubbing the lymph nodes in her collar bone to get them activated. Then the nodes in front of and behind the ears. Then the eyes both under and in the eyebrow region. She massaged her neck, all of this supposedly to get that pooling lymph fluid to flow back into the lymph system and not puff up tissues where it was collecting.

I am the world's biggest skeptic. This looked like pure horse manure to me. But there I was with puffy eyes and jowls and feeling really odd so I gave it a try. What harm could it do?

Has this restored my face to the tight, jowl free 20 year old I used to be? Not a chance. But it DID make a difference in how I FEEL. And a smidge of a difference in how I look.

All of this to say that it might not be the tamoxifen that is puffing up your face but the effects of other surgeries, or even allergies, that might be doing it. You should consider giving this a try. THe results are not dramatic and not instant. But I can feel when I need to 'do the massage' and I swear I feel better and look a wee bit improved after. If I can find that video I will link it . Think about it, NOT tamoxifen, but other surgeries (although you have no surgeries listed in your bio so I am only guessing).

https://www.youtube.com/watch?v=7H9YrjCv8BI

Hello Pals, I have been taking tamoxifen from past 6 months now. i have suffered mild version of the most common side effects such as pain in bones and hair thinning (which is more than mild, i believe) but the major concern is about the throat. ever since i started with tamox i have developed this hoarse voice and my throat feels painful while swallowing (occasionally and not always). i was ignoring it initially believing it to b a seasonal sore throat like condition which would settle down on its own, but boy, it doesn't seem like going away any time soon and i am just wondering what to do with this. any suggestions would be much much appreciated.

Hi godisone,

I’ve got the same problem and I’m taking a large dose of stomach medicine and still have hoarseness, clearing my throat a lot, and a sore throat, not a regular sore throat. I’d let your doctor know. I’m taking the Tamoxifen with food and not laying down after, and trying not to lay down on a full stomach. I’m worried about permanent throat damage

After three years on Arimidex and tons of SEs...I started Tamox May 12 with just 1/2 a 10g pill every other day and have been viglant about SEs. I did two week of 5mg every other day before 4 weeks of 5mg every day. Started to see some SEs with 5mg every day so stayed at that level until SEs had diminished. I am on my second week of 5, 5, 10, 5, 5, 10 and the SEs are big. Vag discharge, bone pain, I sprained my ankle yesterday as I was avoiding weight on my right leg due to bone pain.

I fell pathetic on this, but plan to reduce back to 5mg every day and hope the SEs go back down.

I am DCIS and the most recent studies came out that 5mg might be sufficient...well, I think the some T is better than no T is going to have to be the way as I can't take 10g even just twice a week.

I see the MO next week and he is expecting that I have been on 10g for nearly three months...I'm sure he won't be thrilled that I am still in the 5/10 mode and looking to go back to simply 5.

With regard to metabolizing the drug...I am not a scientist, but the fact that I see SEs at these low levels means to me that by body IS metabolizing this drug and reacting to it. So maybe 5mg IS sufficient...??? TT