Andriol cycle is absorbed quickly and efficiently. Its bioavailability is 81%. Food intake has no clinically significant effect on the bioavailability of topiramate. Since plasma protein binds to 13-17% of topiramate.After receiving a single dose of 1200 mg the average volume of distribution is 0,55-0,8 l / kg. The value of volume of distribution depends on sex: for women it is about 50% of the values observed in men, which is associated with higher levels of body fat women.
After oral administration, it is metabolized about 20% of the dose. However, in patients receiving concomitant therapy with antiepileptic drugs that induce the enzymes responsible for drug metabolism, the metabolism of topiramate is increased to 50%. Six virtually inactive metabolites have been isolated and identified from the plasma, urine and human faeces. The main route of excretion of unchanged topiramate (70%) and its metabolites are the kidneys. Following oral administration of topiramate plasma clearance of 20 – 30 ml / min. The pharmacokinetics of topiramate is linear, plasma clearance remains constant, and the area under the curve “concentration-time» in the andriol cycle dose range from 100 to 400 mg increases proportionally with dose. In patients with normal renal function in order to achieve stable plasma concentrations may need 4 to 8 days. The value of maximum concentration (Cmax) after repeated oral administration primobolan dosage of 100 mg twice a day averaged 6.76 ug / ml. After receiving multiple doses of 50 and 100 mg twice a day half-life of plasma topiramate averaged 21 hour.
In patients with impaired renal function, moderate and severe plasma and renal clearance of topiramate is reduced , as a consequence may increase the equilibrium concentration of topiramate in plasma when compared with patients having normal renal function. In addition, in patients with impaired renal function, it takes longer to reach equilibrium concentration of topiramate in the blood. Patients with moderate or severe renal insufficiency is recommended to use half the recommended initial and maintenance dose.
Topiramate effectively derived from the plasma by hemodialysis. Long term hemodialysis may reduce the concentration of topiramate in the blood below the quantity required to maintain the anticonvulsant activity. To avoid rapid fall topiramate plasma concentration clenbuterol buy during hemodialysis, may require the appointment of an additional dose of the drug andriol cycle . When dose adjustment should be taken into account:
- dialysis duration,
- the amount of clearance used hemodialysis systems,
- effective renal clearance of topiramate in patients on dialysis.
Plasma clearance of topiramate is reduced by an average of 26% in patients with hepatic insufficiency, moderate or severe. Therefore, patients with hepatic impairment topiramate should be used with caution. In elderly patients without renal disease, the plasma clearance of topiramate is unchanged.
The pharmacokinetics of topiramate in children up to 12 years
The pharmacokinetic parameters of topiramate in children as well as adults receiving this drug as an adjunct therapy, are linear, while its ground clearance is independent of dose, and the equilibrium concentration in the plasma increases proportionally to increasing doses. It should be noted, however, that the clearance of topiramate in children increased, and the period of its half-life is shorter.Consequently, for the same dose per 1 kg of body weight, the plasma concentrations of topiramate in children may be lower than in adults. In children as in adults, antiepileptic drugs anavar vs winstrol that induce hepatic microsomal enzymes which cause a decrease in plasma concentrations of topiramate.
As monotherapy: adults and children older than 2 years of age with epilepsy (including in patients with newly diagnosed epilepsy). In the complex therapy: adults and children older than 2 years with partial or generalized tonic-clonic seizures as well as for the treatment of seizures in the background of Lennox-Gastaut syndrome.
Prevention of migraine in adults. The use of andriol cycle has not been studied for the treatment of acute migraine attacks.
Hypersensitivity to any component of this medication, children up to 2 years.
The use of topiramate for migraine prophylaxis is contraindicated during pregnancy and in women with childbearing potential stored not using reliable methods of contraception.
Pregnancy and lactation
Topiramate showed teratogenic properties in mice, rats and rabbits. In rats, topiramate crosses the placental barrier.
Special-controlled studies be used for the treatment of pregnant women have been conducted. Topiramate may cause harm to the fetus when used in pregnant women. These accounting pregnancies indicate that infants exposed to topiramate in utero during the first trimester of pregnancy have an increased risk of congenital malformations (eg, craniofacial defects, such as cleft lip or palate, hypospadias, and anomalies of the various body systems). These malformations were recorded as the topiramate monotherapy or when used as part of polytherapy.
Data from one of the registers of pregnancies have shown that topiramate monotherapy incidence of major congenital malformations is increased approximately 3-fold compared with the comparison group, not to take anti-epileptic drugs.
Furthermore, it is shown that the risk of teratogenic effects associated with the reception of antiepileptic drugs in the above case of combined therapy, than in the case of monotherapy.