Generic: evening primrose
an herbal product - treats Cardiovascular health, Obesity/weight loss, Raynaud's phenomenon, Pre-eclampsia/high blood pressure of pregnancy, Multiple sclerosis, Attention deficit hyperactivity disorder, Diabetic neuropathy, Asthma, Osteoporosis, Breast cysts, Breast pain, Diabetes, Schizophrenia, Scale-like dry skin, Rheumatoid arthritis, Psoriasis, Breast cancer, Bronchitis, Pre-menstrual syndrome, Chronic fatigue syndrome/post-viral infection symptoms, Atopic dermatitis, and Menopause
SafetyDISCLAIMER: Many complementary techniques are practiced by healthcare professionals with formal training, in accordance with the standards of national organizations. However, this is not universally the case, and adverse effects are possible. Due to limited research, in some cases only limited safety information is available.
Allergy or hypersensitivity to evening primrose oil has not been widely reported. Individuals with allergy or adverse reactions to plants in the Onagraceae family, gamma- linolenic acid, or other ingredients in evening primrose oil should avoid its use. Contact dermatitis (skin rash) is possible.
Side Effects and Warnings
Several reports describe seizures in individuals taking evening primrose oil (EPO). Some of these seizures developed in people with a previous seizure disorder, or in individuals taking EPO in combination with anesthetics. Based on these reports, people with seizure disorders should not take EPO. EPO should be used cautiously with drugs used to treat mental illness such as chlorpromazine (Thorazine®), thioridazine (Mellaril®), trifluoperazine (Stelazine®), or fluphenazine (Prolixin®), due to an increased risk of seizure. Patients who plan to undergo surgery requiring anesthesia should stop taking EPO two weeks ahead of time because of the possibility of seizure.
Other reports describe occasional headache, abdominal pain, nausea, and loose stools in people taking EPO. In animal studies, gamma- linolenic acid (an ingredient of evening primrose oil) is reported to decrease blood pressure. Early results in human studies do not show consistent changes in blood pressure.
Pregnancy and Breastfeeding
Interactions with Drugs
Because of reported seizures in people taking evening primrose oil alone or in combination with certain medications used to treat mental illness, patients should use caution when combining evening primrose oil with medications like chlorpromazine (Thorazine®), thioridazine (Mellaril®), trifluoperazine (Stelazine®), or fluphenazine (Prolixin®). Individuals undergoing surgery requiring general anesthesia may be more sensitive to developing seizures, and should stop taking evening primrose oil two weeks ahead of time. In people with a history of seizures, doses of anti- seizure medications may require adjustment because evening primrose oil may increase the risk of seizures.
An ingredient of evening primrose oil, gamma- linolenic acid, is reported to lower blood pressure in animal studies. Although human studies do not show clear changes in blood pressure, people taking certain blood pressure medications should consult with a healthcare professional before starting evening primrose oil.
Possible interactions may occur with antidepressants, including monoamine oxidase inhibitors (MAOIs) and selective serotonin reuptake inhibitors (SSRIs). Interactions may also occur with the following: antineoplastic agents, anti- obesity agents, antiviral agents, CNS stimulants, drugs metabolized by the liver, gastrointestinal treatments, and neurological agents.
Interactions with Herbs and Dietary Supplements
In animal studies, gamma- linolenic acid (an ingredient of evening primrose oil) is reported to lower blood pressure. Therefore, in theory, evening primrose oil may have effects on blood pressure, and should be used cautiously when combined with other agents that may lower blood pressure.
Theoretically, evening primrose oil may have additive effects when taken concomitantly with thyme, because a fixed combination of thyme fluid extract and primrose root tincture (Bronchicum Tropfen) has been used in studies to treat bronchitis.
Primrose oil may potentially interact with herbs and supplements used to treat arthritis, gastrointestinal disorders, obesity, seizures, viral infections, and psychosis. Primrose oil may interact with stimulants and herbs and supplements that are metabolized in the liver. Antineoplastics may also interact with primrose.