Clonidine dosage

The interaction between clonidine and the trieyelics is established and clinically important. The incidence is uncertain but it is not seen in all patients. Avoid concurrent use unless the effects can be monitored. Increasing the dosage of clonidine may possibly be effective. The clonidine dosage was apparently successfully titrated in 10 out of 11 hypertensive patients already on amitriptyline or imipramine. Only clomipramine, desipramine and imipramine have been implieated so far, but other tricyclics would be expected to behave similarly (amitriptyline, nortriptyline and protriptyline have been shown to interact in animals ). The tetracyclic antidepressants maprotiline and mianserin do not generally appear to interact with clonidine. The isolated case of hypotension with trazodone is of unknown general importance. 

Unlabeled route of administration - Sublingual clonidine, using a dosage of 0.2 to 0.4 mg/day, may be effective in hypertensive patients unable to take oral medication. The onset occurs within 30 to 60 minutes and blood pressure appears to be maintained on a twice daily regimen. 

Renal Impairment-Adjust dosage according to degree of renal impairment and carefully monitor patients. Because only a minimal amount of clonidine is removed during hemodialysis, there is no need to give supplemental clonidine following dialysis. 

Beta-biockers/Other sympathetic nervous system suppressants - When beginning therapy, the -blocker dosage should be equal to 80 to 160 mg/day propranolol in divided doses. If -blockers are contraindicated, use methyidopa 250 to 750 mg twice daily give for at least 24 hours before starting minoxidil due to delay in onset. Clonidine may also be used to prevent tachycardia induced by minoxidil usual dosage is 0.1 to 0.2 mg twice daily. 

Two different patterns of clonidine-induced cardiovascular complications have been described (Swanson et ah, 1995). One is characterized by decreased pulse and BP, often with associated EKG changes, fatigue, and sedation, and responds to a decrease in dosage. The other presents with tachycardia, tachypnea, with or without fever, anxiety, panic, and acute mental status changes, and is often associated with a missed dose or an abrupt taper. This pattern often responds to reinstituting the dosage and slowly tapering as necessary. 

In school-age children, clonidine is usually started at 0.05 mg (half of a O.Olmg tablet) in the morning. If tolerated without difficulty for a few days, an afternoon and then early evening dose can be added. The dosage can be increased in one-quarter to half tablet... 

Because the smallest tablet size for clonidine is currently 0.1 mg, it may be difficult to adjust the dosage for younger children. In such cases, it is possible to compound an oral liquid preparation that permits more accurate adjustment of pediatric doses (Levinson and Johnson, 1992)... 

Clonidine hydrochloride (Catapres), carbamazepine (Tegretol), and methylphenidate (Ritalin) are occasionally useful in intractable cases of migraine. Cyproheptadine (Periactin) may be effective in adults with migraine it is of considerable importance in the treatment of childhood migraine, and many consider it to be the drug of first choice. Dosages range from 4 to 3 mg, three to four times a day, in adults and 4 mg, two to three times a day, in children. 

In patients with history of ocular inflammation, 1% prednisolone acetate, one drop four times a day for 3 to 7 days, can be prescribed prophylactically after Nd YAG. Rarely, a patient without history of inflammation may present with flare or mild cells in the anterior chamber or CME after capsulotomy. This also should be treated with topical steroids in the same manner. Post-YAG elevated lOP can often be prevented by treating the eye with apra-clonidine (lopidine) or other aqueous suppressant topical medication. The recommended dosage is one drop applied before the capsulotomy and one drop immediately after the procedure. Because of the potential risk of a retinal break, patients should receive dilated fundus examinations postoperatively as part of the routine follow-up within 1 to 4 weeks of capsulotomy, or sooner if symptoms develop. 

Clonidine is an a2-adrenergic agonist and can therefore be used effectively in portal hypertension at an average dosage of 0.075-0.3 mg/day. 

Treatment with centrally acting agents is characterized by a relatively high incidence (up to 60% in some studies) of nervous system depressant effects (dizziness, drowsiness, tiredness, dry mouth, headache, depression), particularly during the initial period of treatment or after dosage increments. Sedation, lethargy, and tiredness are common with clonidine, particularly at the start of treatment (13). 

Others have reported good results from the use of clonidine (69,70). Of 25 inpatients physically dependent on methadone, 20 were able to withdraw completely from methadone at the end of 2 weeks. In most patients, 10-11 days of clonidine, in a peak dose of 16 micrograms/kg/day, produced a perceived reduction in symptoms compared with previous attempts to become opioid-free. In these dosages, clonidine significantly reduced standing blood pressure without producing clinical problems. 

Transdermal drug delivery can be used in pediatric patients (1) to avoid problems of drug absorption from the oral route and complications from the intravenous route and (2) to maximize duration of effect and minimize adverse effects of drugs. Unfortunately, the commercially available transdermal dosage forms (e.g., clonidine and scopolamine) are not intended for pediatric patients these would deliver doses much higher than those needed for infants and children. 

Barbiturates Opiates Pentobarbital tolerance test initial detoxification at upper limit of tolerance test decrease dosage by 100 mg every 2-3 days Methadone 20-80 mg orally daily taper by 5-10 mg daily or clonidine 2 mcg/kg three times a day x 7 days taper over additional 3 days... 

The intensity of symptoms depends both on the drug and on its mode of administration, the dosage that the individual has been using, and the time from abrupt discontinuance. Full agonist opioids used IV, which include heroin, cause the most severe withdrawal symptoms. Management involves administration of oral methadone , buprenorphine, or clonidine, with gradual dose tapering. 

Guanabenz (Wytensin, others) is a centrally acting tt2 agonist that decreases BP by a mechanism similar to those of clonidine and gnanfacine. Guanabenz has a half-life of 4 to 6 hours and is extensively metabolized by the liver. Dosage adjustment may be necessary in patients with hepatic cirrhosis. The adverse effects caused by guanabenz (e.g., dry mouth and sedation) are similar to those seen with clonidine. 

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