Skip to main content

AZIDOTHYMIDINE (AZT) / ZIDOVUDINE

 AZIDOTHYMIDINE (AZT) / ZIDOVUDINE 


BRAND NAME:- RETROVIR, ZIDOVIR 100mg cap,50mg/5ml syr ,VIRO-Z , ZIDOMAX , ZYDOWN 100 mg cap, 300 mg tab.



AZT / ZIDOVUDINE is a thymidine analogue,the prototype NRTI. After phosphorylation in the host cell- zidovudine triphosphate selectively inhibits viral reverse transcriptase in preference to cellular DNA polymerase.



PHARMACOKINETICS:- 

The oral absorption of AZT is rapid ,but bioavailability is ~ 65% . It is quickly cleared by hepatic glucuronidation (t½ 1 hr) ; 15-20% of the unchanged drug along with the metabolite is excerted in urine. Plasma proteins  binding is 30% and CSF level ~ 50% of that in plasma. It crosses placenta and is found in milk.


PHARMACODYNAMIC:-

Zidovudine is a nucleoside reverse transcriptase inhibitor (NRTI) with activity against Human Immunodeficiency Virus Type 1 (HIV-1). Zidovudine is phosphorylated to active metabolites that compete for incorporation into viral DNA. They inhibit the HIV reverse transcriptase enzyme competitively and act as a chain terminator of DNA synthesis. The lack of a 3'-OH group in the incorporated nucleoside analogue prevents the formation of the 5' to 3' phosphodiester linkage essential for DNA chain elongation, and therefore, the viral DNA growth is terminated.



MECHANISM OF ACTION:-

Zidovudine, a structural analog of thymidine, is a prodrug that must be phosphorylated to its active 5′-triphosphate metabolite, zidovudine triphosphate (ZDV-TP). It inhibits the activity of HIV-1 reverse transcriptase (RT) via DNA chain termination after incorporation of the nucleotide analogue. It competes with the natural substrate dGTP and incorporates itself into viral DNA. It is also a weak inhibitor of cellular DNA polymerase α and γ.


USED:- 

to slow the progression of disease in patients infected with HIV who have advanced symptoms, early symptoms, or no symptoms at all. This medicine is also used to help prevent pregnant women who have HIV from passing the virus to their babies during pregnancy and at birth.

   It is one of the two optional NRTIs used by NACO for its first line triple drug ARV regimen. Its efficacy as monotherapy in AIDS was confirmed in the past . HIV- RNA titer is reduced to undetectable levels and CD4 count increases progressively. Immune status is improved and opportunistic infections become less common. 



SIDE EFFECTS:-

Common side effects include headaches, fever, and nausea.[5] Serious side effects include liver problems, muscle damage, and high blood lactate levels .


DOSE:- 

ADULTS 300mg BD ; CHILDREN 180mg m² (max 200mg) 6-8  hourly.

Comments

Popular posts from this blog

BOTULINUM TOXIN Uses, Side Effects, and More

 BOTULINUM TOXIN ( A or B ) BRAND NAME:- BOTOX ,DYSPORT  BOTULINUM TOXIN  A and B are highly potent exotoxins produced by Clostridium botulinum that are responsible for ' botulism' ( a type of food poisoning). These neurotoxic proteins cause long- lasting loss of cholinergic transmission by interacting with axonal proteins involved in exocytotic release of Ach. Localized injection of minute quantity of botulinum toxin.  PHARMACODYNAMIC :- Botulinum toxin A inhibits the release of acetylcholine, relieving muscle contraction and spasm associated with many conditions, such as incontinence and dystonia. Cosmetically, botulinum toxin A paralyses muscles in the face to temporarily treat wrinkles. The maximum effects of muscle paralysis occur four to seven days after a dose.When injected at therapeutic doses, botulinum toxin A causes partial chemical denervation of muscle tissue, causing local reduction of muscle activity. Muscle atrophy may result, axonal sprouting may beg...

Clonazepam used, Side effects, Dose, & more

Clonazepam  Brand name:- Lonazepam , Clonapax , Rivotril 0.5, 1.0, 2.0 mg tab. Clonazepam is a benzodiazepine. It works by increasing the action of a chemical messenger (GABA) which suppresses the abnormal and excessive activity of the nerve cells in the brain. Pharmacodynamic:- The pharmacodynamic properties of clonazepam are common among benzodiazepines and include anticonvulsive, sedative, muscle relaxing and anxiolytic effects . Animal data and electroencephalographic investigations in man have shown that clonazepam rapidly suppresses many types of paroxysmal activity including the spike and wave discharge in absence seizures (petit mal), slow spike wave, generalized spike wave, spikes with temporal or other locations, as well as irregular spikes and waves Label . Moreover, the agent can also decrease the frequency, amplitude, duration, and spread of discharge in minor motor seizures Label . Generalized EEG abnormalities are more readily suppressed by clonazepam than are focal ...

CLOMIPHENE CITRATE Uses, Side Effects, and More

 CLOMIPHENE CITRATE BRAND NAME:- CLOMIPHENE, FERTOMED, CLOFERT, CLOME 25,50,100mg tab.  Clomiphene is a selective estrogen receptor modulator (SERM) which treats female infertility. It works by promoting the release of reproductive hormones. This helps stimulate the release of eggs from the ovary (ovulation). PHARMACODYANIMCS:- Clomifene (previously clomiphene) is an orally administered, non steroidal, ovulatory stimulant that acts as a selective estrogen receptor modulator (SERM). Clomifene can lead to multiple ovulation, and hence increase the risk of conceiving twins. In comparison to purified FSH, the rate of ovarian hyperstimulation syndrome is low. There may be an increased risk of ovarian cancer and weight gain. Clomifene is capable of interacting with estrogen-receptor-containing tissues, including the hypothalamus, pituitary, ovary, endometrium, vagina, and cervix. It may compete with estrogen for estrogen-receptor-binding sites and may delay replenishment of intracel...