12.31.08

Herb-Drug Interactions (9)

Posted in Herb-Drug Interactions, Herbs, Weatern Herbs at 10:23 pm by Dr. Pharm Tao

Kava (Piper methysticum) – Levodopa; (Benserazide)

Interaction effect:
Increased number and duration of ‘off’ periods

Reference:
Schelosky L, Raffauf C, Jendroska K, Poewe W. Kava and dopamine antagonism. J Neurol Neurosurg Psych 1995; 58: 639-640.

Kava (Piper methysticum) – Alprazolam; (Cimetidine, terazosin)

Interaction effect:
Lethargy, disorientation for several hours

Suggestions:
Probably no interaction but additive effects

Reference:
Almeida JC & Grimsley EW. Coma from the health food store. Interaction between kava and alprazolam. Ann Int Med 1996; 125: 940-941.

Karela or bitter melon (Momordica charantia) – Chlorpropamide

Interaction effect:
Less glycosuria

Reference:
M Aslam and IH Stockley, Interaction between curry ingredient (karela) and drug (chlorpropamide), Lancet i (1979), p. 607.

Liquorice (Glycyrrhiza glabra) – Prednisolone

Interaction effect:
Glycyrrhizin decreases plasma clearance, increases AUC; increases plasma concentrations prednisolone

References:
M-F Chen, F Shimada and H Kato et al., Effect of oral administration of glycyrrhizin on the pharmacokinetics of prednisolone, Endocrinol Jpn 38 (1991), pp. 167–175.
M-F Chen, F Shimada and H Kato et al., Effect of glycyrrhizin on the pharmacokinetics of prednisolone following low dosage of prednisolone hemisuccinate, Endocrinol Jpn 37 (1990), pp. 331–341.

AUC = area under the concentration/time curve

Permalink Comments

12.30.08

Herb-Drug Interactions (8)

Posted in Herb-Drug Interactions, Herbs, Weatern Herbs at 1:08 pm by Dr. Pharm Tao

Ginseng (Panax spp) – Alcohol

Interaction effect:
Increased alcohol clearance

Reference:
FC Lee, JH Ko, JK Park and JS Lee, Effects of Panax ginseng on blood alcohol clearance in man, Clin Exp Pharmacol Physiol 14 (1987), pp. 543–546.

Green tea (Camelliasinensis) – Warfarin

Interaction effect:
Possible decrease in warfarin’s effects

Reference:
Heck AM, DeWitt BA, Lukes AL. Potential interactions between alternative therapies and warfarin. Am J Health Syst Pharm. 2000 Jul 1;57(13):1221-7.

Guar gum (Cyamopsis tetragonolobus) – Metformin, phenoxymethylpenicillin, glibenclamide

Interaction effect:
Slows absorption of digoxin, paracetamol, and bumetanide; decreases absorption of metformin, phenoxymethylpenicillin, and some formulations of glibenclamide

Reference:
PAGM De Smet and PF D’Arcy, Drug interactions with herbal and other non-toxic remedies. In: PF D’Arcy, JC McElnay and PG Welling, Editors, Mechanisms of drug interactions, Springer-Verlag, Berlin (1996).

Horse chestnut – Warfarin

Interaction effect:
Potential increase in risk of bleeding

Reference:
Heck AM, DeWitt BA, Lukes AL. Potential interactions between alternative therapies and warfarin. Am J Health Syst Pharm. 2000 Jul 1;57(13):1221-7.

Permalink Comments

12.29.08

Herb-Drug Interactions (7)

Posted in Herb-Drug Interactions, Herbs, Weatern Herbs at 1:36 pm by Dr. Pharm Tao

Ginkgo (Ginkgo biloba) – Thiazide diuretic

Interaction effect:
Hypertension

Reference:
PAGM De Smet and PF D’Arcy, Drug interactions with herbal and other non-toxic remedies. In: PF D’Arcy, JC McElnay and PG Welling, Editors, Mechanisms of drug interactions, Springer-Verlag, Berlin (1996).

Ginkgo (Ginkgo biloba) – Trazodone; (Bromazepam, donepezil, vitamin E discontinued within 3 days)

Interaction effect:
Coma; antiplatelet

Reference:
Galluzi S, Zanetti O, Binetti G, et al. Coma in a patient with Alzheimer’s disease taking low dose trazodone and ginkgo biloba. J Neurol Neurosurg Psych 2000; 68: 679-683.

Ginseng (Panax spp) – Warfarin; (Diltiazem nitroglycerin, salsalate)

Interaction effect:
Decreased INR; Possible decrease in warfarin’s effects

INR = international normalised ratio

Reference:
K Janetzky and AP Morreale, Probable interaction between warfarin and ginseng, Am J Health Syst Pharm 54 (1997), pp. 692–693.
Heck AM, DeWitt BA, Lukes AL. Potential interactions between alternative therapies and warfarin. Am J Health Syst Pharm. 2000 Jul 1;57(13):1221-7.

Ginseng (Panax spp) – Phenelzine; (Lorazepam triazolam, bee pollen)

Interaction effect:
Headache and tremor, mania

Reference:
RI Shader and DJ Greenblatt, Phenelzine and the dream machine— ramblings and reflections, J Clin Psychopharmacol 5 (1985), p. 65.
BD Jones and AM Runikis, Interaction of ginseng with phenelzine, J Clin Psychopharmacol 7 (1987), pp. 201–202.

Permalink Comments