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Tamosin Side Effects

Generic Name: tamoxifen

Note: This document contains side effect information about tamoxifen. Some of the dosage forms listed on this page may not apply to the brand name Tamosin.

For the Consumer

Applies to tamoxifen: oral solution, oral tablet

Because of the way this medicine acts on the body, there is a chance that it might cause unwanted effects that may not occur until months or years after the medicine is used. Tamoxifen increases the chance of cancer of the uterus (womb) in some women taking it. Tamoxifen may cause blockages to form in a vein, lung, or brain. In women, tamoxifen (the active ingredient contained in Tamosin) may cause cancer or other problems of the uterus (womb). It also causes liver cancer in rats. In addition, tamoxifen has been reported to cause cataracts and other eye problems. Discuss these possible effects with your doctor.

Along with its needed effects, tamoxifen may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking tamoxifen:

Less Common or Rare

  • Anxiety
  • blistering, peeling, or loosening of the skin and mucous membranes
  • blurred vision
  • cataracts in the eyes or other eye problems
  • change in vaginal discharge
  • chest pain
  • chills
  • confusion
  • cough
  • dizziness
  • fainting
  • fast heartbeat
  • fever
  • hoarseness
  • lightheadedness
  • lower back or side pain
  • pain or feeling of pressure in the pelvis
  • pain or swelling in the legs
  • pain, redness, or swelling in your arm or leg
  • painful or difficult urination
  • rapid shallow breathing
  • shortness of breath or trouble with breathing
  • skin rash or itching over the entire body
  • sweating
  • weakness or sleepiness
  • wheezing
  • vaginal bleeding
  • yellow eyes or skin

Incidence Not Known

  • Bloating
  • constipation
  • darkened urine
  • diarrhea
  • difficulty with breathing
  • indigestion
  • itching
  • joint or muscle pain
  • large, hard skin blisters
  • large hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, and sex organs
  • loss of appetite
  • nausea
  • pain in the stomach or side, possibly radiating to the back
  • red, irritated eyes
  • red skin lesions, often with a purple center
  • sore throat
  • sores, ulcers or white spots in the mouth or on the lips
  • unusual tiredness or weakness
  • vomiting

Some side effects of tamoxifen may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More Common

  • Absent, missed, or irregular periods
  • decrease in the amount of urine
  • feeling of warmth
  • menstrual changes
  • noisy, rattling breathing
  • redness of the face, neck, arms and occasionally, upper chest
  • skin changes
  • stopping of menstrual bleeding
  • swelling of the fingers, hands, feet, or lower legs
  • troubled breathing at rest
  • weight gain or loss
  • white or brownish vaginal discharge

Less Common or Rare

  • Abdominal or stomach cramps
  • black, tarry stools
  • bleeding gums
  • blood in the urine or stools
  • bluish color changes in skin color
  • bone pain
  • decreased interest in sexual intercourse
  • discouragement
  • feeling sad or empty
  • hair loss or thinning of the hair
  • headache
  • inability to have or keep an erection
  • irritability
  • itching in the genital area
  • loss of interest or pleasure
  • loss in sexual ability, desire, drive, or performance
  • nausea or vomiting (mild)
  • pain
  • pinpoint red spots on the skin
  • skin rash or dryness
  • stomach or pelvic discomfort, aching, or heaviness
  • swelling
  • trouble concentrating
  • trouble with sleeping
  • unusual bleeding or bruising

For Healthcare Professionals

Applies to tamoxifen: compounding powder, oral solution, oral tablet

Genitourinary

Very common (10% or more): Amenorrhea (16%), altered menses (13%), vaginal bleeding, vaginal discharge

Common (1% to 10%): Oligomenorrhea, menstrual disorder, ovarian cysts, uterine fibroids, pruritus vulvae, endometrial changes (including hyperplasia and polyps)

Uncommon (0.1% to 1%): Endometrial cancer

Rare (less than 0.1%): Suppression of menstruation in premenopausal women, endometriosis, cystic ovarian swelling, vaginal polyps, uterine sarcoma (mostly malignant mixed Mullerian tumors), tumor flare[Ref]

Musculoskeletal

Common (1% to 10%): Bone pain, myalgia, leg cramps[Ref]

Metabolic

Very common (10% or more): Edema

Uncommon (0.1% to 1%): Hypercalcemia (in patients with bone metastases) on initiation of therapy[Ref]

Hepatic

Common (1% to 10%): Changes in liver enzymes, fatty liver

Uncommon (0.1% to 1%): Cirrhosis of the liver

Rare (less than 0.1%): Cholestasis, hepatitis, hepatic failure, hepatocellular injury, hepatic necrosis[Ref]

Hematologic

Common (1% to 10%): Anemia

Uncommon (0.1% to 1%): Thrombocytopenia, leukopenia

Rare (less than 0.1%): Neutropenia, agranulocytosis[Ref]

Ocular

Common (1% to 10%): Cataracts, retinopathy

Uncommon (0.1% to 1%): Visual disturbances

Rare (less than 0.1%): Corneal changes, optic neuropathy[Ref]

Cardiovascular

Common (1% to 10%): Thromboembolic events (including deep vein thrombosis and microvascular thrombosis); risks are increased when used in combination with cytotoxic agents[Ref]

Respiratory

Common (1% to 10%): Cough, thromboembolic events (including pulmonary embolism); risk is increased when used in combination with cytotoxic agents

Uncommon (0.1% to 1%): Interstitial pneumonitis[Ref]

Psychiatric

Common (1% to 10%): Depression[Ref]

Other

Very common (10% or more): Fatigue

Common (1% to 10%): Pain[Ref]

Dermatologic

Very common (10% or more): Skin rash

Common (1% to 10%): Alopecia

Rare (0.01% to 0.1%): Angioedema, Stevens-Johnson syndrome, cutaneous vasculitis, bullous pemphigoid, erythema multiforme

Very rare (less than 0.01%): Cutaneous lupus erythematosus[Ref]

Nervous system

Common (1% to 10%): Ischemic cerebrovascular events, headache, sensory disturbances (including paresthesia and dysgeusia), light-headedness[Ref]

Gastrointestinal

Very common (10% or more): Nausea

Common (1% to 10%): Vomiting, diarrhea, constipation, abdominal cramps, anorexia

Uncommon (0.1% to 1%): Pancreatitis[Ref]

Hypersensitivity

Common (1% to 10%): Hypersensitivity reactions[Ref]

References

1. "Product Information. Tamoxifen Citrate (tamoxifen)." Mayne Pharma Inc, Paramus, NJ.

2. "Product Information. Soltamox (tamoxifen)." Cytogen Corporation, Princeton, NJ.

3. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.

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