Clonidine dosing

Gourlay S, Forbes A, Marriner T, Kutin J, McNeil J. (1994). A placebo-controlled study of three clonidine doses for smoking cessation. Clin Pharmacol Ther. 55(1) 64-69. 

Geriatric Considerations - Summary Discontinuation of clonidine is likely to require a slow taper. If the patient is receiving a concomitant beta-blocker, the beta-blocker must be tapered and discontinued before discontinuing clonidine. Clonidine discontinuation in the presence of a beta-blocker can lead to severe hypertension and cardiovascular events due to unopposed alpha-receptor stimulation. CNS effects often preclude its use in older adults. A higher clonidine dose (0.4 mg/day) is generally needed to control peri- or postmenopausal vasomotor symptoms however, adverse effects often make it difficult to achieve effective doses. 

A 54-year-old hypertensive and diabetic man presented witii intractable neuropathic pain despite intrathecal morphine injection. His medical history included hypertension and diabetes mellitus which he has had for 30 years with complications including pol5meuropathy with bladder dysfunction and erectile dysfunction. Good erectile function had been achieved in the past 5 years on testosterone treatment. He has had intrathecal administration of morphine for 9 years. Despite dose escalation, considerable pain relief had not been achieved. A trial of Ziconotide was stopped because it did not provide any pain relief but ratiier caused severe side effects. A combination of morphine and clonidine was delivered by a programmable pump. Considerable pain relief was achieved in 2 weeks at a clonidine dose of 0.04 mg per day. However, he developed erectile dysfunction and relative hypotension immediately he commenced clonidine because of which he opted to stop clonidine and revert back to morphine monotherapy. Thereafter, erectile dysfunction disappeared and BP reverted back to habitual high levels... 

When clonidine is withdrawn abmpdy, patients may experience a rebound hypertensive phenomenon, whereia blood pressure rises rapidly to a level higher than the predmg level. These patients may experience symptoms of headache, tachycardia, agitation, and nervousness. If rebound hypertension occurs, resumption of clonidine therapy or adrninistration of phentolamine reduces the blood pressure. For clonidine withdrawal, the dose should be reduced gradually over a two-week period. The principal side effects are sedation, dry mouth, drowsiaess, di22iQess, and fatigue. 

Note. Clonidine alone may not adequately treat insomnia, diarrhea, muscle aches, restlessness, irritability, or other withdrawal symptoms, which may require other medications. For this reason many programs use lower doses of clonidine than outlined in this table, in combination with oral... 

Detoxification is more successful when the patient is transitioned from a stable methadone dose with the support of ongoing therapy than when the patient comes directly from the street for detoxification from heroin. Some practitioners believe that detoxification with clonidine can be more rapid than with methadone, at least on an outpatient basis. One important hmitation of clonidine is that, although it suppresses autonomic signs of withdrawal, subject-reported symptoms, such as lethargy, restlessness, insomnia, and craving, are not well relieved (Charney et al. 1981 Jasinski et al. 1985). Anxiety may... 

Cionidine. Clonidine dampens sympathetic activity originating at the locus coeruleus by stimulation of presynaptic a2-adrenergic receptors in the sympathetic chain (Covey and Classman 1991 Hughes 1994). It appears to have some efficacy for alcohol and opioid withdrawal and thus was evaluated for treatment of nicotine withdrawal as well (Covey and Classman 1991 Hughes 1994). Several clinical trials used oral or transdermal clonidine in doses of 0.1—0.4 mg/day for 2—6 weeks with or without behavior therapy. Three meta-analytic reviews reported that clonidine improved quit rates (Covey and Classman 1991 Courlay and Benowitz 1995 Law and Tang 1995). 

Pharmacodynamic interaction clonidine acts as an agonist at a2-receptors, and these TCAs block this receptor to varying degrees the result is an increase in blood pressure either avoid this interaction by choosing another antidepressant or increase the dose of clonidine. 

Nicotine vapor inhaler Buccal Bupropion Oral tablets Clonidine Oral tablets 6-16 mg/day continuous puffing up to 10 puffs per cartridge maximum of 12 cartridges daily (approx. 120 puffs) Begin at 150 mg/day x 3-7 days then 300 mg/day in twice-per-day dosing 0.6-1.2 mg/day, 2-3 times/day... 

T Blood pressure and stimulant Give clonidine or guanfacine 4- Dose or change to another medication Same as above but with baseline and... 

Clonidine Demonstrated efficacy in hot flash reduction in most trials Variety of dose regimens most common 0.1-0.4 mg daily Dry mouth, blood pressure lowering monitor blood pressure... 

The answer is a. (Hardman, p 789. Katzung, pp 162—163.) Withdrawal of clonidine, particularly doses greater than 1 mg/d, is well known to cause such a syndrome (including severe hypertension, tachycardia, anxiety tremor, headache, abdominal pain, and sweating), even after one or two missed doses. 

For treatment of hypertensive rebound after withdrawal of clonidine, 0.2 mg is given initially, followed by 0.2 mg hourly until the DBP falls below 110 mm Hg or a total of 0.7 mg has been administered a single dose may be sufficient. 

Dosing of clonidine initially is 0.1 mg orally twice daily or 0.1 mg/day transdermally, increasing by 0.1 mg/day each week if needed. 

Recent experiments carried out by BOLME and coworkers (39) now raise the question of whether the receptors involved in reducing blood pressure are epinephrine receptors or noradrenaline receptors. These workers found that in rats small doses of yohimbine and piper-oxan blocked the blood pressure lowering effect of clonidine, but did not influence the clonidine-induced increase in flexor reflex activity. This effect on the reflex mechanism is possibly mediated by noradrenaline receptors which can be blocked only by higher doses of a-adrenolytic agents. HtfKFELT et al. (40) consider that epinephrine terminals possibly innervate noradrenaline cell bodies at the locus coeruleus. 

The sedative effects of clonidine were observed in the very first animal experiments performed (HOEFKE and KOBINGER (11)). Obvious symptoms of sedation can be observed on administration of therapeutic doses to dogs, cats, rabbits, rats and mice. Investigations on the mechanism of the sedative action have mainly been performed on chicks. In chicks only a couple of days old the blood-brain barrier is not yet fully developed. 

In contrast to the stimulants that act in a relatively rapid manner, the effects of clonidine are delayed by several weeks. It must be taken regularly and should be started at a dose of 0.05 mg at bedtime for children or 0.1 mg at bedtime for adults. Over several weeks the dose can be increased to a total of 0.3mg/day in three divided doses. 

The most common side effect of clonidine is drowsiness. This can begin with the very hrst dose and usually goes away after a few weeks. Clonidine s sedating effects can actually be useful when it s taken at bedtime. Insomnia is a common problem for patients with ADHD either as a side effect of stimulants or as a consequence of rebound hyperactivity at night when the daytime dose of stimulant has worn off. Clonidine can help the ADHD patient with insomnia to go to sleep. Other side effects of clonidine include low blood pressure, dizziness, depression, dry mouth, nausea, and slowed heart rate. One important point to remember is that not only does clonidine not cause tics, it can, in fact, relieve tics when they appear in patients with ADHD. 

Besides the tablet form, clonidine is also available in a patch that is worn on the arm and changed once every 5-7 days. Once the appropriate dose has been found using oral clonidine, both children and adults can be switched to the patch. The patch provides more consistent levels of the medication and obviously minimizes the potential for rebound effects due to poor compliance. This patch does sometimes cause local skin irritation. Rotating the application site from arm to arm each week can minimize this. 

Antidepressants and clonidine are the most commonly used augmentation strategies for ADHD. If the patient has tics or is troubled by insomnia, clonidine is a reasonable choice. After collecting a baseline EKG, clonidine should be started at 0.05 mg at bedtime for children and adolescents and 0.1 mg at bedtime for adults. The dose can be increased every 2 weeks or so while monitoring the patient s blood pressure and pulse. Although it has not been studied as well, guanfacine may work in much the same manner as clonidine. 

Stimnlants can also canse insomnia. However, insomnia can also result from rebound hyperactivity when the daytime dose of stimulant has worn off In either case, before stopping the stimnlant, it is prudent to consider a bedtime dose of cloni-dine. Clonidine may relieve not only nighttime hyperactivity bnt insomnia as well. 

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