|
|
Coleus* | |
|
Caffeine* Ephedra* | |
|
Magnesium Potassium Vitamin C | |
| Depletion or interference |
None known |
| Side effect reduction/prevention |
None known |
| Reduced drug absorption/bioavailability |
None known |
An asterisk (*) next to an item in the summary indicates that the interaction is supported only by weak, fragmentary, and/or contradictory scientific evidence.
Vitamins and Minerals
Intravenous administration of epinephrine to human volunteers reduced plasma concentrations of
vitamin C.1 Epinephrine and other “stress
hormones” may reduce intracellular concentrations of
potassium and magnesium.2 Although there
are no clinical studies in humans, it seems reasonable that individuals using epinephrine
should consume a diet high in vitamin C, potassium, and magnesium, or should consider
supplementing with these nutrients.
Ephedra
Ephedra is the plant from which the drug ephedrine was originally isolated. Epinephrine and
ephedrine have similar effects and side effects.3 Until 2004, ephedra—also
called ma huang—was used in many herbal products, including supplements promoted for weight loss. While interactions between epinephrine and
ephedra have not been reported, it seems likely that such interactions could occur. To prevent
potential problems, people should not be taking both epinephrine and
ephedra/ephedrine-containing products.
Coleus
A test tube study demonstrated that the bronchodilating effects of salbutamol, a drug with
similar actions in the lung to epinephrine, were significantly increased by the addition of
forskolin, the active component of the herb Coleus forskohlii.4 The
results of this preliminary research suggest that the combination of forskolin and
beta-agonists might provide an alternative to raising the doses of the beta-agonist drugs as
they lose effectiveness. Until more is known, coleus should not be combined with epinephrine
without the supervision of a doctor.
Caffeine
Epinephrine can increase blood pressure and heart rate.5 Caffeine, especially in
large amounts, can also increase heart rate.6 When given with phenylpropanolamine, a drug with effects similar to
epinephrine, caffeine has been shown to produce an additive increase in blood
pressure.7 Caffeine is found in coffee, tea, soft drinks, chocolate, guaraná (Paullinia cupana), nonprescription
drugs, and supplements containing caffeine or guaraná. While no interactions have been
reported between epinephrine and caffeine, people using epinephrine can minimize the potential
for interactions by limiting or avoiding caffeine.
1. Cox BD, Clarkson AR, Whichelow MJ, et al. Effect of adrenaline on plasma vitamin C levels in normal subjects. Horm Metab Res 1974;6:234–7.
2. Raab W. Cardiotoxic effects of emotional, socioeconomic, and environmental stresses. In Myocardiology, vol I, ed. E Bajusz, G Rona. Baltimore: University Park Press 1970, 707–13.
3. Threlkeld DS, ed. Respiratory Drugs, Bronchodilators, Sympathomimetics. In Facts and Comparisons Drug Information. St. Louis, MO: Facts and Comparisons, May 1994, 177–a.
4. Yousif MH, Thulesius O. Forskolin reverses tachyphylaxis to the bronchodilator effects of salbutamol: an in-vitro study on isolated guinea-pig trachea. J Pharm Pharmacol 1999;51:181–6.
5. Threlkeld DS, ed. Respiratory Drugs, Bronchodilators, Sympathomimetics. In Facts and Comparisons Drug Information. St. Louis, MO: Facts and Comparisons, May 1994, 177–a.
6. Threlkeld DS, ed. Central Nervous System Drugs, Analeptics, Caffeine. In Facts and Comparisons Drug Information. St. Louis, MO: Facts and Comparisons, Feb 1998, 230–d.
7. Brown NJ, Ryder D, Branch RA. A pharmacodynamic interaction between caffeine and phenylpropanolamine. Clin Pharmacol Ther 1991;50:363–71.
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