Heme Alkylation: Drugs containing terminal double-bond (olefins) or triple-bond (acetylenes) can oxidized by CYPs to potent radical intermediates, which alkylate the prosthetic heme group and inactivate the enzyme. For example, allyl-isopropylacetamide (AIA) and ethinylestradiol. 2. Covalent Binding to Apoprotein: Covalent bonding of few drugs to apoprotein causes covalent modification of protein which results in loss of catalytic activity, only if essential amino acids are modified (Kamel et. al., 2013).
they have half life time nearly 8-12 hours permitting one dose per day.4,6 Thiazide diuretics were available at the end of 1950 when they had acceptable adverse effect. There are many drugs in this class of diuretics discussed in the following table. Each drug has its own characteristics according to side chains.
Ketamine should be used with caution because of potential interaction between levodopa and ketamine’s sympathomimetic activity. Butryophenones( eg:-droperidol) and phenothiazines , which block dopamine receptors and exacerbate PD should be avoided. Ondansettron appears safe in preventing and treatment of emesis in patients with PD and is also used in treatment of psychosis induced by long term levodopa therapy. Opioids are more succeptible to produce muscle rigidity in patients with PD. Meperidine should be avoided in a patient taking monoamine oxidase inhibitor becaouse of the potential to produce stupor, rigidity, agitation and hyperthermia.
In contrary, the antagonist drugs act as the blocker the way of the body’s natural agonist and also they avoid cell response to agonist. However, these two totally different target receptors can actually be used together. For example, in the case of Asthma. In the respiratory tract, albuterol will stick to the adrenergic receptors so the smooth muscle will relax and expand the airways, also known as bronchodilation. At the same time, the antagonist drugs, ipratropium, attaches to cholinergic receptors and obstruct the attachment of acetylcholine and limit the airways which called bronchoconstriction.
The two most potent classes of antibiotic are the macrolides (azithromycin), and the quinolones (ciprofloxacin, levofloxacin, moxifloxacin, gemifloxacin, trovofloxacin). Other agents that have been shown to be effective include tetracycline, doxycycline, minocycline, and trimethoprim/sulfamethoxazole. Erythromycin, the former antibiotic of choice, has been replaced by more potent and less toxic antibiotics. There are three major classes of antibiotics that are effective in treating legionellosis. These include the fluoroquinolones such as levofloxacin (Levaquin), and moxifloxacin (Avelox), the macrolides such as erythromycin, azithromyocin (Zithromax), and clarithromycin (Biaxin), and the tetracyclines including doxycycline (Vibramycin).
Prolongs levodopa action Useful in wearing off events and motor fluctuations Increases t1/2 of levodopa Increases the availability of levodopa in CNS Useful in advanced cases of Parkinson’s disease Useful in on-off phenomenon Mechanism Intracerebral degradation of dopamine is retarded by inhibition of MAO-B Inhibits metabolism of levodopa by COMT Drug Name MAO-B (Monoamine oxidase B) inhibitors Selegiline Rasagiline COMT (Catecholamine o-methyl transferse) inhibitors Entacapone, Tolcapone Sr No 5. 6. Disadvantages Dizziness, lethargy, anticholinergic effects, and sleep disturbance, Nausea and vomiting Anticholinergic side effects Sedation and mental confusion in elderly more pronounced Advantages Modest anti Parkinsonian effect Can be used as short course with levodopa for motor fluctuations Less side effects compared to
It can be defined as a group of organic chemicals and have been used to hinder the process of oxidative degradation of food products, fats and oils and polymers. Antioxidant can be defined as forms of molecules that help to maintain the body’s chemical reactions. They assist in preventing excessive activity of free radical molecules. Free radicals are molecules that are very reactive;
They also serve as carriers for molecules of low water solubility this way isolating their hydrophobic nature, including lipid soluble hormones, bile salts, unconjugated bilirubin, free fatty acids (apoprotein), calcium, ions (transferrin), and some drugs like warfarin, phenobutazone, clofibrate & phenytoin. For this reason, it's sometimes referred as a molecular "taxi". Competition between drugs for albumin binding sites may cause drug interaction by increasing the free fraction of one of the drugs, thereby affecting
Doxepin inhibits reuptake of monoamines at central synapse. Dosage is 25mg thrice daily which can be gradually increased to 50mg. Selective serotonin reuptake inhibitors inhibit drug metabolizing isoenzymes CYP2D6 and CYP3A4. Dosage for Fluoxetine is 20 mg once daily which can be increased upto 80mg in two divided doses. Sertraline is started as 50mg once daily and increased upto 200mg/day.