By C. Irmak. Washington College.
Plasmodium vivax is the most extensively distributed and causes much debilitatng disease discount combivent 100mcg amex. Recrudes- cence of these infectons results from persistent blood forms in inadequately treated or untreated patents purchase combivent 100mcg without a prescription. Treatment of Malaria: Blood schizontcides, which suppress malaria by destroying the asexual blood forms of the parasites, are the mainstay of the treatment of acute malaria and some are used for prophylaxis. They include the 4-aminoquinolines (example amodiaquine and chloroquine), the related arylaminoalcohols (example mefoquine and quinine) and artemisinin and its derivatves (example artemether and artesunate). Blood schizontcides are not actve against intrahepatc forms and therefore they do not eliminate infectons by P. For example, pyrimethamine in combinaton with a sulfonamide (sulfadoxine) or sulfone and some antbiotcs (for example doxycycline) are blood schizontcides. Because they act more slowly, these substances are of litle value when used alone. The tetracyclines are used primarily as adjuncts to quinine where multple-drug-resistant P. Chloroquine, a rapidly actng schizontcide, is well tolerated, safe and inexpensive. It should preferably be used as part of combinaton therapy with other antmalarials, for example artesunate. Hepatts and blood disorders were reported when amodiaquine was used for prophylaxis of malaria; patents should be told how to recog- nise the symptoms of these conditons and advised to seek medical help if they occur. The combinaton of sulfadoxine with pyrimethamine is recom- mended for the treatment of malaria only in areas of high chloroquine resistance. A single dose of sulfadoxine with pyrimethamine is usually sufcient to eliminate infecton; quinine should also be given for 3 days in patents in whom quinine may accelerate reducton of parasitaemia and in those at risk of fulminatng disease. Because sulfonamides are asso- ciated with a risk of haemolysis and methaemoglobinaemia in the newborn, quinine is preferred to treat chloroquine-re- sistant malaria during pregnancy. Mefoquine is generally well tolerated, although, some adverse efects have been reported (see notes). However, because of the danger of the emergence of mefoquine-resistant strains of P. Doxycy- cline, which is an efectve oral schizontcide, should be given in combinaton with quinine except in pregnant women and children under 8 years. In mult-drug resistant malaria, preparatons of artemisinin or its derivatves (artemether or artesunate) ofer the only prospect of cure. For the treatment of mult-drug resistant falciparum malaria oral artesunate may be an efectve antmalarial. Parenteral artemether or artesunate, whose use is restricted, are efectve alternatves to quinine for the treatment of severe falciparum malaria and are preferred in areas where decreased efcacy of quinine has been documented. To ensure radical cure following parenteral treat- ment with artemether or oral treatment with artesunate, a full therapeutc dose of mefoquine should be given. A fxed-dose oral formulaton of artemether with lumefantrine has recently become available and is recommended for the treatment of uncomplicated falciparum malaria in areas with signifcant resistance. Chloroquine, which is usually well tolerated at the required dosage, is preferred where P. The combinaton of proguanil with chloroquine may overcome mild chloroquine resistance. Chloroquine must be started 1 week before exposure and be contnued in pregnant women untl afer delivery and for at least 4 weeks afer the last risk of exposure in the case of non-immune individuals. Mefoquine may be used for prophylaxis in areas of high risk or where multple-drug resistance has been reported. Where possible prophylaxis should be started 2-3 weeks before travel to enable any adverse reactons to be identfed before expo- sure (over three-quarters of adverse reactons occur by the third dose) and should be contnued for 4 weeks afer last exposure. It should be used in early pregnancy only if alternatve drugs are either not available or unlikely to be efectve and when it is impractcable for the woman to leave the endemic area. Proguanil, a predominantly tssue schizontcide with litle blood schizontcidal actvity, is a causal prophylactc agent since it is actve against pre-erythrocytc intrahepatc forms, partcularly of P. Proguanil is used for prophylaxis with chlo- roquine in areas where there is resistance to chloroquine but a low risk of infecton as it may give some protecton against and may alleviate symptoms if an atack occurs. Proguanil and chloroquine may also be used prophylactcally in areas of high risk or mult-drug resistance as a second choice where mefo- quine is not appropriate. There is no evidence that proguanil is harmful in prophylactc doses during pregnancy. Because of the vulnerablility of preg- nant women to falciparum malaria, it should be used at full prophylactc dosage wherever the disease is prevalent and likely to be responsive to proguanil, if chloroquine is not avail- able or with chloroquine, if the later alone is unlikely to be efectve. Dose Oral Adult- Immediately 600 mg, afer 6 h 300 mg followed by 300 mg daily for 2 days. Child- 10 mg/kg body weight followed by 5 mg/kg body weight afer 6 h, thereafer once a day for 2 days.
With these similarities in manner we feel that it is appropriate to mention here some of the work done on the question of prevarication under the influence of these drugs order 100mcg combivent with visa, which as treated in more detail in Chapter 3 generic 100 mcg combivent. In a study of malingering soldiers Ludwig (42) reports that they remained negativistic and uncommunicative while under drugs. Nevertheless, narcoanalysis, when correctly used, may enable the psychiatrist to probe more deeply and quickly into the psychological characteristics of the subject. Thus the bare results of an interview under the influence of drugs should not, standing alone, be considered a valid and reliable indicator of the facts. We feel that these conclusions apply not only to narcoanalysis but to hypnosis as well. If, as we have proposed, an individual under the influence of these drags is in a state akin to hypnosis, then the results of these drug studies support our theory that some subjects may lie, confabulate, or withhold information while in trance. Even those informants who believe they are telling the truth may in fact be offering a composite of delusion, fantasy, and reality. Thus, the convincing delivery of -195- information obtained under hypnosis may easily lead an interrogator astray. There is no evidence to indicate that this technique is anything more than a convincing form of role-playing, real only on an emotional level. Hypnosis does not improve recall for nonmeaningful material, and does so only slightly for meaningful material. However, there is evidence that emotionally laden material that is not normally accessible can be recovered in hypnosis. Inaccuracies may be the result of deliberate prevarication, or of an unwitting confusion of fantasy and reality. The determination of the truth or falsity of information obtained in hypnosis would have to be based on outside criteria. Defensive Uses of Hypnosis Simulation of Hypnosis An interrogator who employs hypnosis may find that his subject apparently enters trance and gives the desired information. The classical view holds that subjects are unable to deceive experienced hypnotists because hypnotic behavior "looks different" in a number of ways. Furthermore, claims have been made that in order to detect fraud the hypnotist need only suggest anesthesia to the subject and test for it with a painful stimulus. However, there are some indications in the literature that the detection of simulation is not a simple task. For example, Pattie (55), a thoroughly experienced investigator, felt that it was necessary to request his subjects sign forms reading as follows: I, realizing that the experiment performed on me will probably be published in a scientific journal, solemnly declare that I was not faking or imitating the hypnotic trance but that I was genuinely hypnotized and do not remember the events of the experimental periods. He has been unable to discover any physiological indices which differentiate simulators from deeply hypnotized subjects. In addition he also found that the overwhelming majority of apparently naive subjects are capable of simulating well enough to deceive even experienced hypnotists. Regarding pain, Orne (2) found and Shor (68) has confirmed that the simulating subjects generally tolerated higher levels of electric shock than did subjects in deep hypnosis. Using a fairly wide spectrum of behavioral tasks, they found it was not possible to differentiate unequivocally between real and simulating subjects. However, certain kinds of behavior were observed only in the true hypnotic subjects, although not in all of them. Typically, this mixture controverts the rules of logic normally operating in the waking state. For example, a subject might describe an hallucination of an individual sitting in a chair as "I can see Mr. However, trance logic helps discriminate neither those real subjects who do not manifest this behavior nor those simulators who have been taught to demonstrate it. Considerable research remains to be done on the recognition of simulating behavior. At our present state of knowledge it is vital to bear in mind that the deep hypnosis is essentially a clinical diagnosis. Although under some circumstances this diagnosis can be made with a high degree of reliability, definitive signs of deep trance have not yet been identified. Until such pathognomic signs are developed, a subject trained to employ trance logic may not find it too difficult to deceive an interrogator. Training in Hypnosis in Anticipation of Future Interrogation Three related suggestions have been made for what may be called the defensive use of hypnosis. Thus, Estabrooks (22) proposed that hypnosis might be useful in (a) preventing subsequent trance induction in captured personnel, (b) causing personnel possessing sensitive information to develop amnesia for this material in case of capture, and (c) enabling captured personnel to resist stressful and painful -197- interrogations by training them to develop anesthesia and analgesia when required. Any objective evaluation of these proposals is made difficult by the paucity of relevant studies, and we are forced to extrapolate from the meager evidence available. In judging the practicality of these suggestions it is necessary first of all to take into account that only approximately 20%, of the military population can be expected to go into a sufficiently deep somnambulistic state conducive to such training.
In many cases it appears 30 minutes to 1 hour following the application and is dependent on the substance and on its concentration best combivent 100 mcg. The tear film is destabilized when the surface tension of the instilled solution is much lower than the surface tension of the lacrimal fluid discount 100 mcg combivent visa. The normal osmolality of tears varies from 290 to 310 mOsmkg−1, which is almost equivalent to that of normal saline solution. Variations in osmotic pressure between 100– 640 mOsmkg−1 appear to be well tolerated by the eye; beyond these values irritation takes place, eliciting reflex tears and reflex blinking. When the eye surface is covered with a hypotonic solution the permeability of the epithelium is increased considerably and water flows into the cornea. The corneal tissues swell, increasing the pressure on the nerves and causing an anesthetizing action on the cornea. In the case where the eye surface is covered with hypertonic solution, water flows from the aqueous layer through the cornea to the eye surface. A desquamation of superficial cells is also observed after instillation of hypertonic solution in rabbits. Although the instillation of a non-isotonic solution will cause a change in tear osmolality, it will regain the original value within 1 to 2 minutes following dosing. In general, however, hypotonic solutions are well tolerated in the eye and can lead to better corneal absorption of the drug due to a concentration effect on the formulation and increased permeability of the cornea (both by virtue of uptake of water from the formulation by the corneal tissue). Conjunctival absorption is nonproductive and constitutes an additional loss following instillation of a topical dose. Most drugs cross this membrane into the intraocular tissues by either intercellular or transcellular diffusion. Lipophilic drugs are transported via the transcellular route, and hydrophilic drugs penetrate mainly through the intercellular 305 Figure 12. There is little evidence that ophthalmic drugs penetrate into ocular compartments by active transport. In general, corneal penetration is mainly governed by the lipophilicity of the drug but it is also affected by other factors, including solubility, molecular size and shape, charge and degree of ionization. These pathways and the factors affecting the absorption by these mechanisms are discussed in detail in Section 1. There are three pathways for drug penetration across the sclera: • through the perivascular spaces; • through the aqueous media of gel-like mucopolysaccharides; • through the empty spaces within the collagen network. The noncorneal route is usually not productive, as drug penetrating the surface of the eye beyond the corneal- scleral limbus is picked up by local capillary beds and removed to the general circulation. This route in general precludes drug entry into the aqueous humor, which would have an impact on ocular drug delivery. It is interesting that the noncorneal route of absorption may be important for hydrophilic compounds with large molecular weights such as timolol maleate and gentamicin. This route may also be attractive in 306 potentially facilitating the transport of peptides and proteins, either as drugs or drug carriers, to their target sites within the eye. A drop is placed in the inferior cul-de-sac by gently pulling the lower lid away from the globe and creating a pouch to receive the drop. After gently lifting the lid to touch the globe, a small amount of liquid is entrapped in the inferior conjunctival sac, where it may be retained up to twice as long as when it is simply dropped over the superior sclera. Drainage from the cul-de-sac may further be reduced by punctual occlusion or simple eyelid closure, which not only maximizes the contact of drug with the periocular tissues but also slows the rate of the systemic absorption. Following dosing, the normal manoeuvre results in a gradient across he eye as illustrated in Figure 12. This suggests that dosing under the upper lid would improve delivery: however, this method of dosing would be difficult for the patient. The local/systemic effect balance can be improved by reducing the size of the eyedrop and tips capable of delivering a drop of 8–10 μl have been designed by varying the relationship between the inner and outer diameters of the end of the tip. The use of smaller eye droppers results in a reduced systemic drug absorption, but their use in commercial containers has not been popular. Although a smaller drop may be retained longer in the conjunctival sac, the instilled volume less than 8 μl is not recommended due to the difficulty in making up a suitable concentration for the eyedrop. The process of passive diffusion initially involves partition of a drug between the aqueous fluid at the site of the application and the lipoidal cell membrane. The drug in solution in the membrane then diffuses across the membrane followed by a second partition of drug between the membrane and the aqueous fluids within the site of absorption. Two approaches can be used to enhance corneal drug permeability: • modify integrity of the corneal epithelium transiently; • modify the chemical structure of the drug. Flow from the lacrimal gland dilutes the concentration of drug in the tear film pulled up from the lower marginal strip The first approach can be accomplished by exposing the eye to compounds such as chelating agents and surfactants, but it has hardly been explored due to the sensitivity of this particular tissue. The second approach commonly focuses on changing the physicochemical properties of the drug, such as lipophilicity, solubility and pKa. Physicochemical factors associated with the drug moiety The physicochemical properties of a molecule which affect its absorption across the cornea are broadly the same as those affecting transepithelial absorption at any site and have been discussed extensively in Chapter 1 (Section 1.
High-performance liquid chromatography synthetic hypoglycemic drugs added illegally to ‘natural’ quadrupole time-of-fight mass spectrometry method anti-diabetic herbal products generic combivent 100mcg with mastercard. Chromatographia effective combivent 100mcg, for the analysis of antidiabetic drugs in aqueous envi- 70:1353–1359. Rosiglitazone and risk of cancer: a meta-anal- Piccinni C, Motola D, Marchesini G, Poluzzi E (2011). Hazardous Substances Data Bank: National Radhakrishna T, Sreenivas Rao D, Om Reddy G (2002a). Biochem Biophys Res method for the simultaneous analysis of diltiazem, Commun, 278(3):704–11. Co-solvent solubilization urine by liquid chromatography/tandem mass spec- of some poorly-soluble antidiabetic drugs. Selective and validated spectro- cancer: a population-based cohort study in Taiwan. Int J human studies: is it diabetes itself, diabetes drugs, Clin Pract Suppl, (121):13–8. Determination of piogli- a population-based cohort study using the National tazone in dog serum using solid-phase extraction and Health Insurance in Taiwan. Diabetes Res Clin Simultaneous estimation of six anti-diabetic drugs– Pract, 98(1):159–63. Multi-component plasma quantitation of anti-hyperglycemic pharmaceutical compounds using liquid chromatography-tandem mass spectrometry. Quantitative determination of pioglita- zone in human serum by direct-injection high-perfor- mance liquid chromatography mass spectrometry and its application to a bioequivalence study. High-performance liquid chromatographic determination of pioglitazone and its metabolites in human serum and urine. Exposure Data Te Working Group noted that most of what has been used under the term “digitalis” in North America and Europe has been digoxin; Digoxin is a cardiac glycoside isolated from however, there may be parts of the world where plants of the genus Digitalis. William Withering published his monograph “An account of the foxglove and some of its medical uses” (Withering, 1785; Albrecht & Geiss, 2000). Furthermore, 3-[(O-2,6-dideoxy-β-D-ribo-hexopyranosyl- the term “digitalis use” found in many reports -(1→4)-O-2,6-dideoxy-β-D-ribo-hexo- probably refers not to the use of plant mate- pyranosyl-(1→4)-2,6-dideoxy-β-D-ribo- rial, which is not commercially available as a hexopyranosyl)oxy]-12,14-dihydroxy-, medicinal product, but to the use of the isolated (3β,5β,12β)- (SciFinder, 2013) compounds. Te Working Group 4,5-dihydroxy-6-methyloxan-2-yl] estimated that digoxin represents at least 90% of oxy-4-hydroxy-6-methyloxan-2-yl]oxy-4- the world market for digitalis glycosides. Tus, studies reporting thren-17-yl]-2H-furan-5-one (PubChem, use of “digitalis” should be carefully scrutinized 2013) since the agent to which people were actually Synonyms: 12β-hydroxydigitoxin exposed could have been any one of the four digitalis glycosides. Te purity of digoxin is pressure, 760 Torr) (SciFinder, 2013) 382 Digoxin typically at least 95% (see Section 1. Name: 3β-[(O-2,6-dide- glucosidase enzymes at 30–37 °C until glucose oxy-β-D-ribo-hexopyranosyl-(1→4)-O-2,6- is completely removed. Extraction procedures, dideoxy-β-D-ribo-hexopyranosyl-(1→4)- usually followed by precipitation of tannic 2,6-dideoxy-β-D-ribo-hexopyranosyl) acid and related phenolic products with lead oxy]-14-hydroxy-4β,14β-card-20(22)-enolide. Compendial methods to determine digoxin and digitoxin in pharmaceutical preparations 1. For detection in (a) Indications human plasma or urine, liquid chromatography Digoxin and digitoxin are therapeutically the with mass spectrometric detection is required to most widely used digitalis glycosides. Te lists the most commonly reported clinical indica- analytical methods are summarized in Table 1. Digoxin is generally maintenance therapy because its long half-life less efective than other drugs in producing (5 – 9 days) provides a sustained therapeutic efect consistent reduction of heart rate, particularly even if a dose is missed. For congestive heart failure, use of digoxin (b) Dosage fails to improve survival (Digitalis Investigation Group, 1997) when compared with placebo, Administration is typically oral, although unlike other leading therapies. It does, however, preparations for intravenous administration provide symptomatic benefts in some cases exist. Typically, digoxin is used orally for months and is associated with reduced risk of hospital- to years, while intravenous use requires careful ization. Te absorption ratio was found to be angiotensin-converting-enzyme inhibitors and 70%, the decay ratio is 20%, the efective dose β-blockers) fail to produce adequate symptom level is 2 mg, and the maintenance dose is 0. Most generic tablet preparations of digoxin Globally, there are 160 licensed products average 70–80% oral bioavailability, with containing digoxin, while there are only seven 90–100% oral bioavailability for digoxin elixir licensed products containing digitoxin in and the encapsulated gel preparation. Parenteral Germany, Austria, Hungary, and Norway (Index digoxin is available for intravenous administra- Nominum, 2013). Caution to avoid over- strategies, cardiac glycosides are still widely used, dosing is necessary in elderly patients or those and digoxin belongs to the 10 most frequently with renal impairment (Li-Saw-Hee & Lip, 1998). Other nations tions may be correlated to the range of available reporting appreciable use of digoxin included tablet strengths. Afer leaf-tissue damage or for cancer of the breast (Stenkvist, 1999; Haux, plant harvest, the primary glycoside lanatoside C 1999); however, because so little information is converted to the secondary glycoside digoxin was provided and larger studies with stronger by the endogenous enzyme, digilanidase, present designs were available, these early studies were in the leaves, and by subsequent deacetylation. Environmental factors that infuence the digoxin Varied designs were used in these studies. Te Digoxin is specifed in several ofcial phar- studies describing “digitalis” use are therefore macopoeias (Table 1. Data on before diagnosis was compared in 109 hyper- risk factors were limited to information available tensive women with cancer of the breast and in physician interviews by mail or telephone, and in 109 matched hypertensive women without clinical record reviews.
9 of 10 - Review by C. Irmak
Votes: 53 votes
Total customer reviews: 53