Clonidine Ethanol

Procedure Dissolve 0.2 g of clonidine hydrochloride in 70 ml of ethanol (96%) and titrate with 0.1M ethanolic sodium hydroxide Vs determining the end-point potentiometrically. Each ml of 0.1 M ethanolic sodium hydroxide Vs is equivalent to 26.66 mg of C9H9C12,N3, HC1. 

Franks FIM, Flagedorn FI, Flensley VR, Flensley WJ, Starmer GA. (1975). The effect of caffeine on human performance, alone and in combination with ethanol. Psychopharmacologia. 45(2) 177-81. Franks P, Flarp J, Bell B. (1989). Randomized, controlled trial of clonidine for smoking cessation in a primary care setting. JAMA. 262(21) 3011-13. 

Some toxicants that affect body temperature are shown in Figure 6.11. Among those that increase body temperature are benzadrine, cocaine, sodium fluoroacetate, tricyclic antidepressants, hexachlorobenzene, and salicylates (aspirin). In addition to phenobarbital and ethanol, toxicants that decrease body temperature include phenothiazine, clonidine, glutethimide, and haloperidol. 

Page 94, figure 10.9 Simplified after data from Journal of Pharmacology And Experimental Therapeutics 306 271-8 (2003), Maas M.M. et al. Effects of chronic ethanol feeding on clonidine-evoked reductions in blood pressure, heart rate, and their variability time-domain analyses. 

Tyramine present in certain food and beverages can displace NE from sympathetic nerve endings, causing CV stimulation, but only if its metabolism is inhibited by MAO inhibitors. Patients suffering from HTN commonly discontinue medications (without physician consultation) based on perceived undesirable side effects, such as sexual dysfunction. In the case of clonidine, rebound hypertension and tachycardia, especially with abrupt discontinuance, can be problematic. Discontinuance of thiazide is likely to result in fluid retention with weight gain and unlikely to cause tachycardia and marked increase in BP. Ethanol is an effective vasodilator and tends to decrease BP. Tachyphylaxis refers to the development of a decreased response to drug treatment over a time span of minutes to hours, not years. 

Tricyclic drug interactions (Table 30-3) include additive depression of the CNS with other central depressants, including ethanol, barbiturates, benzodiazepines, and opioids. Tricyclics may also cause reversal of the antih)pertensive action of guanethidine by blocking its transport into sympathetic nerve endings. Less commonly, tricyclics may interfere with the antihypertensive actions of methylnorepinephrine (the active metabolite of methyl-dopa) and clonidine. 

Opioids (especially methadone and heroin) are the most common cause of serious neonatal drug withdrawal symptoms. Other dmgs for which a withdrawal syndrome has been reported include phencyclidine (POP), cocaine, amphetamines, tricyclic antidepressants, phenothiazines, benzodiazepines, barbiturates, ethanol, clonidine, diphenhydramine, lithium, meprobamate, and theophylline. A careful dmg history from the mother should include illicit drugs, alcohol, and prescription and over-the-counter medications, and whether she is breast-feeding. 

C. Anecdotal reports suggest that high-dose naloxone may partially reverse the central nervous system and respiratory depression associated with clonidine (see p 169), ethanol (see p 190), benzodiazepine (see p 130), or valproic acid (see p 362) overdoses, although these effects are inconsistent. 

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