Guanfaцin

When ATH:
C02AC02

Characteristic.

Antihypertensive (central alpha₂-adrenomimetik). Guanfacina hydrochloride is a white or almost white powder. It is soluble in water and ethanol, slightly soluble acetone. Molecular weight 282,56.

Pharmacological action.
Gipotenzivnoe, alpha adrenomimeticheskoe.

Application.

Arterial hypertension.

Contraindications.

Hypersensitivity, hypotension, AV block II and III degrees, recent myocardial infarction, vыrazhennaya bradycardia, depression, concomitant use of tricyclic antidepressants.

Restrictions apply.

Asequence, coronary insufficiency, cerebral atherosclerosis, a history of depression, obliterating peripheral arterial disease, sinusovaya bradycardia, chronic liver dysfunction, Age to 18 years (data on the efficacy and safety of missing).

Pregnancy and breast-feeding.

In experiments on rats and rabbits at doses, in 70 and 20 times higher than MRDC, guanfatsina adverse effects on the fetus have been identified.

When pregnancy is possible, if the effect of therapy outweighs the potential risk to the fetus (adequate and well-controlled studies in pregnancy in humans is not carried out).

Category actions on the fetus by the FDA — B. (The study of reproduction in animals revealed no risk of adverse effects on the fetus, and adequate and well-controlled studies in pregnant women have not done.)

Guanfacine gets into the milk of lactating rats. Gets whether guanfacine in women's breast milk, unknown, but any related problems are not registered.

Side effects.

From the nervous system and sensory organs: drowsiness / insomnia, headache, dizziness, unusual tiredness or weakness, confusion, depression, conjunctivitis.

Cardio-vascular system and blood (hematopoiesis, hemostasis): orthostatic hypotension, bradycardia.

From the digestive tract: dry mouth, nausea or vomiting, constipation.

Other: increased perspiration, nasal congestion, fluid retention; syndrome, similar to Raynaud's syndrome, allergic reactions, decreased libido and / or potency.

Cooperation.

Sympathomimetics and non-selective alpha-blockers (phentolamine, yohimbine hydrochloride) weaken the effect, Diuretic, beta-blockers, peripheral vazodilatatora — amplify. In combination with beta-blockers (except preparations, possess intrinsic sympathomimetic activity) increased risk of bradycardia. At the same time taking NSAIDs, especially indomethacin, antihypertensive activity may weaken guanfatsina (indomethacin, perhaps, NSAIDs can counteract the appearance of antihypertensive effect, suppressing PG synthesis in kidney and / or causing retention of sodium and fluids). In a joint application with estrogens may increase blood pressure (Estrogens cause fluid retention). With the simultaneous use of alcohol or drugs, cause CNS depression, possible mutual reinforcement of CNS depression.

Overdose.

Symptoms: labored breathing, expressed dizzy or faint, slowing heartbeat, expressed unusual tiredness or weakness, disturbance of consciousness, collapse.

Treatment: gastric lavage, simptomaticheskaya therapy.

Dosing and Administration.

Inside, adult, initial dose is 0.5-1 mg 1 once a day at bedtime. If necessary, the daily dose was increased to achieve the desired level of blood pressure reduction. To increase or decrease the dose should be gradually, not more than 1 mg (or 50% starting from) in Week. The highest daily dose - 6 mg 1 reception at night (less often 2 admission).

Precautions.

During treatment, must be constantly at regular intervals of time to monitor blood pressure. After 2-7 days after discontinuation of the possible development of withdrawal (signs and symptoms of sympathetic hyperactivity). During treatment, the concentration of catecholamines and vanillylmandelic acid in the urine may be reduced, but the sudden cancellation of the drug may increase. The content of the growth hormone in plasma may temporarily increase due to the stimulation of secretion, but long-term use does not increase long guanfatsina notes.

It should be remembered, that elderly patients may be more sensitive to the hypotensive and sedative effect guanfatsina. It should be closely monitored for the sick, NSAIDs are applied simultaneously, especially indomethacin, in order to ensure the achievement of the desired effect.

You may need to control body weight and diet (especially salt intake). If the decrease in blood pressure are not maintained for 24 no, more effective use can be divided doses, but this increases the likelihood of side effects. To reduce daytime sleepiness need to take the drug at bedtime.

Application guanfatsina may reduce / suppress salivation, which contributes to the development of caries, periodontal tissue diseases, oral candidiasis and the appearance of unpleasant sensations in the mouth.

During treatment should avoid the use of ethanol, as well as employment, requiring attention and quick response.

Cooperation

Active substance	Description of interaction
Alprazolam	FMR: synergism. Strengthens (mutually) sedation.
Buprenorphine	FMR: synergism. Sedative effect.
Buspirone	FMR: synergism. Strengthens (mutually) sedation.
Haloperidol	FMR: synergism. Strengthens (large doses) sedation.
Gidroksizin	FMR: synergism. Strengthens (mutually) sedation.
Diazepam	FMR: synergism. Strengthens (mutually) sedation.
Droperidol	FMR: synergism. Strengthens (large doses) sedation.
Zolpidem	FMR: synergism. Sedative effect.
Izofluran	FMR: synergism. Against the backdrop of intensified guanfatsina deprimatsiya.
Quetiapine	FMR: synergism. Strengthens (large doses) sedation.
Ketamine	FMR: synergism. Against the background of enhanced effects guanfatsina.
Klozapyn	FMR: synergism. Strengthens (large doses) sedation.
Codeine	FMR: synergism. Sedative effect.
Lorazepam	FMR: synergism. Strengthens (mutually) sedation.
Midazolam	FMR: synergism. Sedative effect.
Morphine sulfate	FMR: synergism. Sedative effect.
Oxazepam	FMR: synergism. Strengthens (mutually) sedation.
Olanzapine	FMR: synergism. Strengthens (large doses) sedation.
Perfenazyn	FMR: synergism. Strengthens (large doses) sedation.
Propofol	FMR: synergism. Against the background of enhanced effects guanfatsina.
Risperidone	FMR: synergism. Strengthens (large doses) sedation.
Sotalol	FMR: synergism. Against the background of enhanced effects guanfatsina, incl. unwanted (y ou usugubitysya bradycardia, develop intracardiac conduction blockade).
Tioridazin	FMR: synergism. Strengthens (large doses) sedation.
Trifluoperazine	FMR: synergism. Strengthens (large doses) sedation.
Phenytoin	FKV. Accelerates biotransformation, significantly reduces T1/2 and plasma concentration.
Phenobarbital	FKV. FMR. Accelerates biotransformation, significantly reduces T1/2 and plasma concentration; at the same time may increase sedation.
Fentanyl	FMR: synergism. Sedative effect.
Flufenazin	FMR: synergism. Strengthens (large doses) sedation.
Xlordiazepoksid	FMR: synergism. Strengthens (mutually) sedation.
Chlorpromazine	FMR: synergism. Strengthens (large doses) sedation.
Chlorprothixene	FMR: synergism. Strengthens (large doses) sedation.