Evening Primrose
  Uses of this Herb
Chronic Fatigue Syndrome
Congestive Heart Failure
Diabetes Mellitus
Headache, Migraine
Multiple Sclerosis
Premenstrual Syndrome (PMS)
Radiation Damage
Raynaud's Phenomenon
Rheumatoid Arthritis
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Look Up > Herbs > Evening Primrose > Interactions
Interactions with Evening Primrose

In rat studies, evening primrose oil (EPO) offered protection from cyclosporine-induced renal dysfunction (Morphake et al. 1994). Rats fed standard chow containing 10 mL/kg EPO (representing 9% gamma-linolenic acid and 72% cis-linolenic acid) developed fewer lesions than untreated animals following 7 days of treatment with cyclosporine (45 mg/kg/day intraperitoneally).


A double-blind cross-over study involving 13 chronic inpatients or day patients with schizophrenia evaluated the effects of EPO (4 g) as an adjunct to treatment (Holman and Bell 1983). No significant therapeutic effects were associated with EPO. However, grand mal seizures occurred in two patients, indicating that EPO may enhance the epileptogenic properties of phenothiazines. EPO is contraindicated in patients taking phenothiazines because of the potential for lowering the seizure threshold and increasing the risk of seizures in this patient population (Shaw et al. 1991).


Holman CP, Bell AFJ. A trial of evening primrose oil in the treatment of chronic schizophrenia. J Orthomol Psychiatry. 1983;12:302-304.

Morphake P, Bariety J, Darlametsos J, et al. Alteration of cyclosporine (CsA)-induced nephrotoxicity by gamma linolenic acid (GLA) and eicosapentaenoic acid (EPA) in Wistar rats. Prostaglandin Leukot Essent Fatty Acids. 1994;50:29-35.

Shaw D, Leon C, Kolev S, Murray V. Traditional remedies and food supplements; a 5-year toxicological study (1991-1995). Drug Safety. 1997;17(5):342-356.

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