The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.
Avoid in individuals with a known allergy or hypersensitivity to S-adenosyl-L-methionine. Flushing, erythema (reddening of the skin), palpitation, dizziness, and nausea (symptoms of an anaphylactic reaction) have been reported.
Side Effects and Warnings
SAMe has been well tolerated in the majority of clinical trials conducted. The most common adverse effects reported are gastrointestinal in nature with nausea being the most frequently reported. Skin rashes have also been reported. Anxiety and hypomania have been reported mainly in trials that have included patients with bipolar disorder. The use of SAMe has not been adequately studied in the pediatric and elderly population, in pregnancy other than the third trimester, or during breastfeeding.
When given as an injection, diluted SAMe has caused superficial phlebitis (inflammation of a vein) and tachycardia (increased heart rate), increased perspiration, transient pain at the injection site, arm soreness, flushing, erythema (reddening of the skin), palpitation, dizziness, nausea, pruritus (itching), urticaria ("hives"), and epigastric pain.
SAMe may lower blood sugar levels. Caution is advised in patients with diabetes or hypoglycemia, and in those taking drugs, herbs, or supplements that affect blood sugar. Serum glucose levels may need to be monitored by a qualified healthcare professional, including a pharmacist, and medication adjustments may be necessary.
When taken by mouth or by injection, SAMe may cause a hot sensation and itchiness of the ear, nausea, vomiting, dry mouth, heartburn, blood in the stool, anorexia, mild diarrhea, stomachaches, slight constipation, increased thirst, increased salivation, urinary frequency, intolerable bowel symptoms, gas, and decreased appetite. Anxiety, insomnia, hypomania, hostility, insomnia, elevated mood, psychoactivation, headache, suicidal ideation, hyperactivity, a reduced need for sleep, and bursts of energy have also been reported.
Pregnancy and Breastfeeding
SAMe crosses the placenta. SAMe is not recommended in the first trimester or during breastfeeding due to a lack of available scientific evidence. However, SAMe has been used in the third trimester for the treatment of intrahepatic cholestasis with no reported adverse effects in the pregnant women or their newborn babies. A single study of SAMe included women in second trimester with no adverse effects noted. Use cautiously in women in their third trimester of pregnancy; SAMe should only be used in pregnancy if the benefits clearly outweigh the risks.