michigan hypertension core curriculum - State of Michigan

1- Fludrocortisone : a mineralocorticoid that helps retain sodium and water, thereby partially
compensating for vascular tone that inappropriately high for normal intravascular volumes
2- Midodrine : an α-adrenergic agonist that causes vasoconstriction and increases peripheral
vascular resistance. This medication is particularly effective in patients with noradrenergic
denervation, and should probably be avoided in the evening to avoid further worsening of
supine hypertension. Other alpha-adrenergic agonists that have been used include ephedrine,
pseudoephedrine, and phenylephrine.
3- Yohimbine, a centrally and peripherally acting α-2 adrenoceptor antagonist, increases
sympathetic nervous system efferent output by antagonizing central or presynaptic a2-
adrenoreceptors. Side effects of yohimbine include anxiety, tremor, palpitations, diarrhea and
supine hypertension
4- Clonidine, predominantly a presynaptic α-2 adrenoceptor agonist, has a sympatholytic effect
in normal individuals by decreasing catecholamine release. Clonidine has lesser affinity for
postsynaptic α-1 adrenoceptors, but this effect can normally be seen only at high doses (> 1 mg
per day). However, in patients with neurogenic OH and markedly diminished central efferent
sympathetic activity, the postsynaptic affects may predominate. The drug needs to be used with
caution since it can exacerbate hypotension in some patients.
5- Droxidopa (L-threo-3,4-dihydroxyphenlyserine or L-DOPS) has been reported to improve OH.
It has been suggested that droxidopa may be less likely to exacerbate supine hypertension
than standard pressor drugs such as midodrine. The drug appears to replete postganglionic
adrenergic axons, thereby restoring physiologic control of supine BP. It also seems to improve
OH even where there is a severe loss of postganglionic fibers (as in pure autonomic failure)
thereby suggesting an extraneuronal mode of action as well.
6- Non-selective beta blockers, such as propranolol, result in unopposed stimulation of peripheral
α-1 receptors.
7- Desmopressin, a vasopressor that helps constrict peripheral vessels and may increase cerebral
and coronary blood flow
8- Pyridostigmine, a cholinesterase inhibitor that increases ganglionic trafficking in proportional
response to orthostatic stress
9- SSRI antidepressants
220 Hypertension Core Curriculum