Limited studies have evaluated drug-drug interactions for etanercept. Concomitant treatment with methotrexate, warfarin, or digoxin does not significantly affect the pharmacokinetic profile of etanercept (Zhou 2005). This is particularly important in the case of methotrexate, which is often given concomitantly with etanercept in patients with rheumatoid arthritis. A pharmacokinetic modeling study reported that etanercept absorption, bioavailability, volume of distribution, and clearance were similar in patients receiving etaner-cept monotherapy and in those receiving combination therapy with etanercept and methotrexate (Zhou et al. 2004a). Digoxin reduced the mean peak concentration of etanercept by 4.2 and the area under the curve by 12.5 . This attenuation was not considered to be clinically relevant (Zhou 2005). Likewise, etanercept does not significantly affect the pharmacokinetics of any of these agents (methotrexate, warfarin, or digoxin) therefore, no dosage adjustment must be...
Use with caution in lactation, with impaired hepatic function, or if receiving drugs known to influence hepatic metabolism. Safety and efficacy have not been established in children. Side Effects The following side effects are common to alpha-1-adren-ergic blockers. See individual drugs as well. Oral Dry mouth. CV Palpitations, postural hypotension, hypotension, tachycardia, chest pain, arrhythmia. GI N&V, diarrhea, constipation, abdominal discomfort or pain, flatulence. CNS Dizziness, depression, decreased libido, sexual dysfunction, nervousness, paresthesia, somnolence, anxiety, insomnia, asthenia, drowsiness. Musculoskeletal Pain in the shoulder, neck, or back gout, arthritis, joint pain, arthralgia. Respiratory Dyspnea, nasal congestion, sinusitis, bronchitis, broncho-spasm, cold symptoms, epistaxis, increased cough, flu symptoms, pharyngitis, rhinitis. Ophthalmic Blurred vision, abnormal vision, reddened sclera, conjunctivitis. GU Impotence, urinary frequency,...
Depending on the etiology, pain may be present in 1,2, or more joints. Considering the patient's age, medical history, and medication profile is important. The patient's lifestyle and social history should also be considered, as certain activities may predispose a patient to specific infections. Among the major diagnoses that have to be considered in a nontraumatic swollen joint are gout (or any crystal-induced arthritis), infectious arthritis, osteoarthritis, and rheumatoid arthritis. A short discussion on low back pain is included.
Azathioprine is a 6-mercaptopurine derivative that acts as a false metabolite in the proliferation of bone marrow stem cells. The typical dose is 1 to 2 mg kg per day, adjusted to maintain a white blood cell count greater than 5000 mm3. The most common side effect is bone marrow suppression manifest as neutropenia. In some patients, anemia and thrombocytopenia may be present. The most common drug interaction is with allopurinol, which may be prescribed to treat acute gouty arthritis, itself a side effect of cyclosporine therapy. if allopurinol is to be prescribed, the dose of azathioprine should be decreased by half and frequent follow-up white blood cell counts should be obtained to avoid profound bone marrow suppression.
In switching drugs, the half-life of elimination that is being stopped should be considered if drug interactions are to be avoided. The time taken for the withdrawal of a drug depends on the duration of treatment sedatives, antiepileptics and anxiolytics may take several weeks to withdraw.
Ensure that the patient understands the need to rest every hour, space work out over several days, and get at least 8 hours of sleep at night. Ensure that the patient knows whom to call in the event of sudden severe pain (as in a subluxation) or general worsening of the existing condition. Determine whether a home care agency needs to evaluate the home for safety equipment, such as rails and grab bars, and whether ongoing supervision is required. Instruct patients on salicylates that they may need periodic laboratory monitoring of liver and kidney functioning and that they should consider drug interactions. Review patient medication regimen for interactions with salicylates. Some drugs that potentially are affected by salicylates include anticoagulants, corticosteroids, nonsteroidal anti-inflammatory drugs (NSAIDs), urine acidifiers, furosemide, para-aminobenzoic acid, certain antacids, phenobarbital, methotrexate, sulfonylureas, insulin, beta-adrenergic blockers, spironolactone, and...
Additional Side Effects Severe bone marrow depression. Hepatotox-icity, fibrosis, cirrhosis. Hemorrhagic enteritis, intestinal ulceration or perforation, acne, ecchymosis, hemateme-sis, melena, increased pigmentation, diabetes, leukoencephalopathy, chronic interstitial obstructive pulmonary disease, acute renal failure. Intrathecal use may result in chemical arachnoiditis, transient paresis, or seizures. Concomitant exposure to sunlight may aggravate psoriasis. Drug Interactions Alcohol, ethyl Additive hepatotox-icity combination can result in coma
Tacrine, donepezil, rivastigmine and galantamine are cholinesterase inhibitors which preserve endogenous acetylcholine following its synthesis. The inhibition of the cholinesterase may be either reversible, irreversible or pseudo-irreversible. In addition, the inhibitor may be either competitive or non-competitive for true (acetyl) cholinesterase, pseudo (butyryl) cholines-terase or for both types. Some anticholinesterases also have a weak affinity for the nicotinic cholinergic receptors. These drugs also differ in their pharmacokinetic properties (for example, protein binding, elimination halflife and in their drug interactions).
Drug Interactions Cimetidine T Effect of paroxetine due to l breakdown by the liver Diazepam T Half-life of diazepam MAO inhibitors Possibility of serious, and sometimes fatal, reactions including hyperthermia, rigidity, myoclonus, autonomic instability with possible rapid fluctuations in VS, and mental status changes including extreme agitation progressing to delirium and coma Phenobarbital Possible l effect of paroxetine due to T breakdown by the liver
As regards long-term toxicity, particularly nephro-toxicity, and frequent drug interactions, the benefit-to-harm balance of ciclosporin is still debatable. Whereas the adverse effects have generally been deemed acceptable, although occasionally treatment-limiting in patients with rheumatoid arthritis given low-dose ciclosporin rather than conventional antirheumatic drugs, conflicting opinions have been expressed on the acceptability of the risks in patients with psoriasis (SEDA-20, 343). Drug interactions with ciclosporin have been comprehensively reviewed (5).
People should use oxycodone cautiously if they are also taking antihistamines, various antidepressants, or a monoamine oxidase inhibitor (MAOI, found in some antidepressants and other medicine). Combining those sorts of drugs with oxycodone can produce excessive effects. The same is true of alcohol. Oxycodone also seems to interact with cyclosporine, a substance used to suppress an individual's immune system (an effect useful in preventing rejection of organs in transplant patients).
An experiment found that eating licorice reduces testosterone levels in men, enough that the candy may contribute to problems of male sexual function. Adolescent hamsters that drink alcohol show elevated testosterone levels, and a human study showed high levels among some alcoholics. Testosterone impairs blood clotting, which may dangerously boost actions from medicines given to reduce blood clots.
Depression is a frequently missed diagnosis in the elderly. The Alliance for Aging Research says that 15 of Americans aged 65 years and older experience clinically relevant depression. It can amplify the underlying disabilities in stroke, arthritis, Parkinson's disease, slow or prevent recovery from hip fracture and surgery, and be mimicked or masked by an underactive thyroid. The latest receptor-specific medicines have a very much reduced potential for adverse events and drug interactions. Difficulties can arise from confusion, memory impairment and disorientation, which are common in the depressed elderly. This brings challenges of ensuring both drug compliance and follow-up attendance in clinical studies. It also may require guardian co-signature for informed witnessed consent.
Hormone use in male-to-female transsexuals, beside having its pros and cons in itself, may complicate the treatment of HIV and AIDS. Addressing the use of hormones enables the clinician to correctly calculate the dosing schedule of drugs, to monitor complications accurately, and to achieve desired therapeutic effects while reducing unwanted complications. The clinician must also be on the lookout for drug interactions and the risk of breast and possibly other cancers, all of which may be affected by hormones, and must monitor the unknown effect of estrogens and progestins themselves on immune response.
Pausal women, during lactation, or in pediatric clients. Concurrent use with systemic estrogen or hormone replacement therapy. Special Concerns Use with caution with highly protein-bound drugs, including clofibrate, diaze-pam, diazoxide, ibuprofen, indo-methacin, and naproxen. Effect on bone mass density beyond 2 years of treatment is not known. Side Effects CV Hot flashes, migraine. Body as a whole Infection, flu syndrome, chest pain, fever, weight gain, peripheral edema. CNS Depression, insomnia. GI Nausea, dyspepsia, vomiting, flatulence, GI disorder, gastroenteritis. GU Vaginitis, urinary tract infection, cystitis, leukorrhea, endometrial disorder. Respiratory Sinusitis, pharyngitis, increased cough, pneumonia, laryngitis. Musculoskeletal Arthral-gia, myalgia, leg cramps, arthritis. Dermatologic Rash, sweating. Drug Interactions Ampicillin l Absorption of ampi-cillin
Side Effects CV Hypotension, chest pain, palpitations, angina pec-toris, MI, arrhythmias. Oral Dry mouth. GI N&V, abdominal pain, diarrhea, dysgeusia, anorexia, constipation, dyspepsia, enzyme changes suggesting pancreatitis, dyspha-gia, gastroenteritis, increased salivation. CNS Headache, dizziness, fatigue, insomnia, sleep disturbances, somnolence, depression, nervousness, malaise, vertigo, anxiety, amnesia, convulsions, tremor. Respiratory Cough, dyspnea, upper respiratory tract infection, asthma, bronchospasm. Hematologic Leuko-penia, eosinophilia. Rarely, decreases in hemoglobin or hematocrit. Der-matologic Diaphoresis, photosensitiv-ity, pruritus, rash, dermatitis, purpura. Body as a whole Paresthesias, angioedema, asthenia, syncope, fever, muscle cramps, myalgia, arthral-gia, arthritis, neuralgia, neuropathy, influenza, edema. Miscellaneous Impotence, tinnitus, hearing loss, vision disturbances, epistaxis, weight gain, proteinuria. Drug Interactions See also...
Paracetamol is the most commonly used analgesic. A single 1000 mg dose of paracetamol provides 50 pain relief over 4-6 hours in moderate or severe pain compared with placebo. There are virtually no contraindications, significant drug-drug interactions or side effects at the recommended dosage. It is well tolerated by patients with peptic ulcers. Despite many years of use, the mechanism of action of paracetamol is not well understood. It may be centrally active, producing analgesia by elevating the pain threshold through prostaglandin synthetase inhibition in the hypothalamus. At therapeutic dosages it does not inhibit prostaglandin synthetase in peripheral tissues, so has no anti-inflammatory activity.
Respiratory Bronchitis, cough, dyspnea, epistaxis, hemoptysis, laryngitis, pharyngitis, pneumonia, respiratory disorder rhinitis, sinusitis, URTI. GU Enlarged prostate, vaginal discharge, micturition disorder, UTI. Dermatologie Acne, dermatitis, seborrheic dermatitis, eczema, erythema, folliculitis, furunculosis, hair changes, hot flushes, photosensitivity reaction, changes in skin pigment, maculopapular rash, skin disorder, skin nodules, skin ulceration, increased sweating, urticaria, verruca, xeroderma. Ophthalmic Dry eye syndrome, xerophthalmia, blepharitis, eye irritation, visual disturbance. Otie Earache, ear pressure, decreased hearing, otitis, tinnitus. Drug Interactions Astemizole Possibility of prolongation of QT intervals serious CV adverse effects
Musculoskeletal Arthritis, arthralgia, myalgia. Dermatolog-ic Rash, skin lesion, diaphoresis. Other Blurred vision, visual disturbances, nystagmus, tinnitus, hearing loss, lupus-like syndrome. Drug Interactions No specific interactions have been reported with drugs that are used in dentistry. However, lowest effective dose should be used, such as a local anesthetic, vasoconstrictor, or anticholi-nergic, if required. How Supplied Tablet 400 mg, 600 mg
Receptor binding potency, antiretroviral activity, and pharmacokinetic properties through this process, maraviroc was identified as the lead clinical candidate 91 . Compound screening was further enhanced by the use of a high-throughput binding assay for the hERG potassium channel, to reduce the chances of QT interval prolongation 92 . Studies in HIV-uninfected volunteers were conducted to explore pharmacokinetics and drug-drug interactions 93 . Investigators conducting the first study in HIV-infected patients gave maraviroc at eight different dosing schemes to 63 participants and reported dose-dependent antiretroviral activity and no safety concerns 94 . With further clinical development, two cases of hepatotoxicity in patients taking mar-aviroc were reported, but neither was clearly related to the study drug 95 .
If a change in mental status or delirium has precipitated the evaluation, consider infections, seizures, and drug interactions or toxicities. Check thyroid function, carnitine levels (especially if patient is on valproic acid), and serum drug levels. Anticholinergics, antihistamines, and benzodiazepines are frequently associated with delirium and agitation.
Evidence of different profiles of side effects and drug-drug interactions among the quinolones - the pharmacokinetic standpoint. Chemotherapy 2001 47 Suppl 3 24-31, discussion 44-8. 103. Stass H, Kubitza D. Profile of moxifloxacin drug interactions. Clin Infect Dis 2001 32 Suppl 1 S47-50. 112. Pea F, Furlanut M. Pharmacokinetic aspects of treating infections in the intensive care unit focus on drug interactions. Clin Pharmacokinet 2001 40 833-68. 181. Lee AJ, Maddix DS. Rhabdomyolysis secondary to a drug interaction between simvastatin and clarithromycin. Ann Pharmacother 2001 35 26-31. 186. Eadie MJ. Clinically significant drug interactions with agents specific for migraine attacks. CNS Drugs 2001 15 105-18. 239. Penning van Beest FJ, Van Meegen E, Rosendaal FR, Stricker BH. Drug interactions as a
Major considerations in the clinical development of a site-specific system, relating to effect, utility, and efficacy could include Novel pharmacokinetic and disposition Novel modalities of cell tissue receptor exposure Utilization of novel cellular transport processes Species-specific drugs and delivery modalities Novel drug interactions Novel drug metabolism Local versus general distribution Biphasic drug action Chronopharmacoloy
NSAIDs bind avidly to plasma proteins. High protein binding can theoretically predispose patients to drug interactions, which occur most frequently with certain NSAIDs (for example the butazones) in patients who are concomitantly taking drugs such as hypoglycemic agents or oral anticoagulants. The unbound fraction responsible for the pharmacological action of NSAIDs varies with the plasma albumin concentrations, which can be influenced by active rheumatoid arthritis, genetic factors, sex, age, pregnancy, other drugs, and diseases, particularly when the kidney and liver are involved. A correlation between anti-inflammatory action and dose or plasma concentration has been documented for only a few NSAIDs, and there is no direct evidence that an increase in unbound drug concentration is associated with greater toxicity. However, there is convincing evidence that the dose contributes to certain adverse effects (for example gastrointestinal and renal). A record-linkage study has shown an...
DRUG INTERACTIONS As do other NSAIDs, the propionic acid derivatives may interfere with the action of antihypertensive and diuretic agents, increase the risk of bleeding with warfarin, and increase the risk of bone marrow suppression with methotrexate. Ibuprofen also has been
Treatment of superficial fungal infections of the skin is best achieved with topical broad spectrum antifungals such as ciclopirox or azoles, applied twice daily. In severe inflammatory disease, it is helpful to start with combination therapy including topical corticosteroids for 3 or 4 days, to achieve quick relief of discomfort. Deep infections and infections involving terminal hairs (tinea capitis, tinea barbae) require systemic treatment with griseofulvin (500-1000 mg day), terbinafine (250 mg day), fluconazole (50 mg day), or itraconazole (100-400 mg day). There are different regimens to treat onychomycosis. Itraconazole (pulse therapy) and terbinafine (250mg per day) are typically used for two months for fingernails and three months for toenails. Griseofulvin may be used for up to 9 months or longer, until the infection clears (Aly 1996, Myskowski 1997, Gupta 2000). If only the distal part of the nail plate is infected, topical treatment with nail varnish containing antifungals...
Only one disease at a time rather than the medication list as a whole. Instead, for geriatric inmates the best way to minimize polypharmacy is to review the entire medication list, to add new medications cautiously, and to regularly assess the need for each medication while considering the possibility of drug-drug interactions with other concurrent medications (Landefeld et al., 2004). One approach would be to create a geriatrics clinic to periodically assess older adults with multiple medical conditions and or disability.
INDUCTION OF DRUG METABOLISM Xenobiotics can influence the extent of drug metabolism by activating transcription and inducing the expression of genes encoding drug-metabolizing enzymes. Thus, a drug may induce its own metabolism. One potential consequence of this is a decrease in plasma drug concentration as the autoinduced metabolism of the drug exceeds the rate at which new drug enters the body, resulting in loss of efficacy. Ligands and the receptors through which they induce drug metabolism are shown in Table 3-4. Figure 3-5 shows the scheme by which a drug may interact with nuclear receptors to induce its own metabolism. A particular receptor, when activated by a ligand, can induce the transcription of a battery of target genes, including CYPs and drug transporters. Any drug that is a ligand for a receptor that induces CYPs and transporters could cause altered drug metabolism and drug interactions. polymorphisms of metabolic enzymes are identified and potential drug interactions...
Hematologic Leukocytosis, lymphadenopa-thy, thrombocytopenia. Metabolic nutritional Weight gain or loss, peripheral edema, lower extremity edema, dehydration, hyperglycemia, hyperkalemia, hyperuricemia, hypo-glycemia, hypokalemia, hyponatre-mia, ketosis, water intoxication. Musculoskeletal Joint pain, extremity pain, twitching, arthritis, back and hip pain, bursitis, leg cramps, myas-thenia, rheumatoid arthritis. Dermat-ologic Vesiculobullous rash, alopecia, contact dermatitis, dry skin, eczema, hirsutism, seborrhea, skin ulcer, urticaria. Ophthalmic Amblyopia, blepharitis, corneal lesion, cataract, diplopia, dry eyes, eye hemorrhage, eye inflammation, eye pain, ocular muscle abnormality. Otic Deafness, ear pain, tinnitus. Miscellaneous Diabetes mellitus, goiter, cyanosis, taste perversion. Drug Interactions Carbamazepine T Clearance of olanzepine due to T rate of metabolism
Further details can be obtained from Note for Guidance of Non Clinical Safety Studies for the Conduct of Human Clinical Trials for Pharmaceuticals (FPMP ICH 286 1995) Note for Guidance on the Investigation of Drug Interactions (CPMP EWP 560 95, approved Dec. 1997) and Standard Guidance ICH Topic S7A CPMP ICH 539 00.
Patients with hyperuricemia who excrete less than 1 g 24 hr are considered to be underexcreters and can be treated with a uricosuric agent instead of allopurinol unless they have nephrolithiasis, tophi, or renal failure. Probenecid (Benemid), the most commonly used uricosuric agent, is started at 250 mg twice a day for a few days, then increased to 500 mg twice a day, and gradually increased up to a total of 3 g day if needed. The goal of therapy is to get the serum uric acid below 6.0 mg dL (360 mol L), although a level of 5 mg dL (300 mol L) or less more effectively dissolves uric acid crystals. Gastric intolerance to probenecid is fairly common, and many drug interactions occur for example, aspirin eliminates the uricosuric effect of probenecid. The cost of probenecid is also slightly higher than that of allopurinol. For this reason, many clinicians prefer to use allopurinol even in underex-creters. It is effective against any form of hyperuricemia.
And even acute toxicity can develop after long symptom-free usage. Hema-tologic Methemoglobinemia, hemolytic anemia, neutropenia, thrombocy-topenia, pancytopenia, leukopenia. Allergic Urticarial and erythematous skin reactions, skin eruptions, fever. Miscellaneous CNS stimulation, hypo-glycemic coma, jaundice, drowsiness, glossitis. GI Nausea, vomiting, abdominal pain, hepatotoxicity. Drug Interactions Barbiturates T Potential of hepatotoxicity due to T breakdown of acetaminophen by liver NSAIDs T Nephrotoxicity with concurrent, chronic high dose use Salicylates T Nephrotoxicity with concurrent, chronic high dose use Tetracycline T Decreased absorption due to T buffer in buffered acetaminophen
By paclitaxel administered in a 24-hr infusion induced a 33 reduction in the clearance rate of paclitaxel and a more profound neutropenia than the reverse drug sequence in a Phase I study. 13 This finding can be explained by the reduction in CYP3A4 activity produced by cisplatin, although the mechanisms responsible for this sequence-dependent drug-drug interaction are not entirely understood. Enhanced vincristine toxicity was observed in two patients with acute lymphoblastic leukaemia who concomitantly received itraconazole, which inhibits CYP3A4 activity. 14 The CYP3A4-induc-ing antiepileptic agents carbamazepine, phenytoin, and phenobarbital decreased the steady-state paclitaxel concentration and toxicity in patients with glioblastoma multiforme, leading to a 42 higher maximum tolerated paclitaxel dosage in patients who received the antiepileptic agent, compared to that in patients who did not receive any of these agents. 15 These antiepileptic agents also increased the systemic...
John's wort are similar to those of SSRIs and include gastrointestinal symptoms, dizziness, confusion, sedation, dry mouth, photosensitivity, and induction of hypomania according to Barrette, in 2000, and PDR for Herbal Medicines in 2000. A number of drug interactions may occur with St. John's wort. It can reduce blood levels of the HIV drugs (such as indinavir) by more than 50 , which may in turn lead to drug-resistant strains of the virus, noted the University of California, Berkeley, in 2000. It reduces the effects of blood thinners such as warfarin (Coumadin), the heart drug digoxin, some oral contraceptives, and the immunosuppressant drug cyclosporine (which helps prevent organ rejection in transplant recipients). It increases photosensitivity when used in conjunction with other photosensitizing drugs.
Side Effects Oral Dry mouth, taste changes, tooth disorder. The following side effects occurred in greater than 2 of the population studied GI Dyspepsia, diarrhea, abdominal pain, nausea, flatulence. CNS Headache, insomnia, dizziness. CV Peripheral edema. Pulmonary URTI, sinusitis, pharyngitis, rhinitis. Der-matologic skin rash. Neuromuscular Back pain. Miscellaneous Accidental injury. Drug Interactions Aspirin T Risk of GI bleeding Fluconazole T Celecoxib levels How Supplied Capsules 100 mg, 200 mg
Trasystoles, syncope, migraine, hypotension. Hematologic Agranulocytosis. Body as a whole Asthenia, flu syndrome, back pain, malaise, abdominal pain, acute abdominal syndrome, chills, fever, facial edema, photosensitivity reaction, neck rigidity, neck pain, enlarged abdomen. Respiratory Dyspnea, increased cough, sinusitis, epistaxis, bronchitis, asthma, pneumonia. GU Urinary frequency, UTI, kidney calculus, cystitis, dysuria, urinary incontinence, urinary retention, vaginitis, hematuria, breast pain, amenorrhea, dysmenorrhea, leukorrhea, impotence. Musculoskeletal Myalgia, my-asthenia, arthralgia, arthritis, tenosyno-vitis. Dermatologic Pruritus, rash, acne, exfoliative dermatitis, dry skin, herpes simplex, alopecia. Metabolic nutritional Increased appetite, weight gain, peripheral edema, edema, thirst, dehydration, weight loss. Ophthalmic Eye pain, abnormal accommodation, conjunctivitis, kerato-conjunctivitis, lacrimation disorder, glaucoma. Miscellaneous Deafness, hyperacusis, ear...
Drug interactions Aspirin Patients with arthritis and vascular disease sometimes take both low-dose aspirin and other NSAIDs. However, concomitant treatment with ibuprofen may limit the cardioprotective effects of aspirin, according to the results of a study of the effects of ibuprofen, diclofenac, coxibs, and paracetamol on the antiplatelet activity of aspirin (33C). The following combinations of drugs were used aspirin (81 mg every morning) 2 hours before ibuprofen (400 mg every morning) or in the reverse order aspirin 2 hours before rofe-coxib (25 mg every morning or in the reverse order) enteric-coated aspirin 2 hours before ibuprofen (400 mg tds) and enteric-coated aspirin 2 hours before modified-release diclofenac (75 mg bd). Inhibition of the formation of serum thromboxane B2 (an index of COX-1 activity in platelets) and platelet aggregation by aspirin was blocked when a single daily dose of ibuprofen was given before aspirin, as well as when multiple daily doses of ibuprofen...
Drug interactions Methotrexate Methotrex-ate is often prescribed for the management of rheumatoid arthritis, and some NSAIDs have been reported to interact, causing increased plasma concentrations associated with impaired renal function. The safety of concurrent rofe-coxib and oral methotrexate has been studied for 3 weeks in 25 patients with rheumatoid arthritis (119c). Rofecoxib 12.5-50 mg day had no effect on the plasma concentrations or renal clearance of methotrexate, but supratherapeutic doses of rofecoxib (75 and 250 mg) caused a significant increase in the plasma methotrexate AUC and reduced renal clearance.
Rats that receive ethylestrenol are better able to survive massive exposure to meprobamate or nicotine and high exposure to the insecticides paraoxon and parathion. Ethylestrenol also makes rats act less affected by LSD. Ethylestrenol can counteract anesthesia actions of barbiturates, diminish ulcers caused by the pain reliever indomethacin, and reduce consequences of vitamin D overdose.
Propoxyphene's actions can be impeded if a person smokes tobacco cigarettes. Propoxyphene can lengthen the time span of effects produced by alprazolam and diazepam. Studies have found that blood levels from a dose of the epilepsy medicine carbamazepine will be higher if a person also takes propoxyphene, possibly high enough to cause harm. Propoxyphene should be used with particular caution if a person is also using alcohol, antidepressants, antihistamines, or tranquilizers. Conceivably the alcohol-propoxyphene combination could seriously impair driving skills, although scientists testing various mental and physical performance effects of the combination found that alcohol had more impact than propoxyphene.
A private survey of 19 pharmaceutical companies operating in the USA (Chaponis, 1998) ranked cardiovascular, depression, Alzheimer hypertension, rheumatoid arthritis osteoarthritis, and oncology as the most important therapeutic areas in their company. All of these are commonly found in the elderly. Why did companies target these therapeutic areas in the geriatric population This drew the response 'It's a growing population,' from 77 of respondents, and 'increasing market size' from 58 of the 27 company respondents. Companies were asked which types of geriatric-based clinical trials they conducted. Safety, efficacy, pharmaco-kinetic- and drug interaction studies were quoted in that order of frequency, which, because of the introduction of the guidelines, is to be expected. However, the next most frequent studies were qual-ity-of-life, pharmacoeconomic, drug disease (outcomes) and patient satisfaction studies. The later studies reflect the elderly and third-party payers' influences...
The following list is intended for informational purposes only. It does not include all medications you may be taking, and it does not cover all possible side effects, drug interactions, or uses of the medication. If you develop symptoms not mentioned or if you have questions, contact your doctor, nurse, or pharmacist.
In situations where pronounced differences in potency exist and the less or inactive enantiomer is metabolically converted to the active enantiomer, as in the case of some 2-arylpropionic acid derivatives, the use of the active enantiomer instead of the racemate might be advantageous. The administration of the active (S)-enantiomer of 2-arylpropionic acid derivatives would circumvent interindividual variability in the metabolic conversion of the inactive to the active enantiomer. In addition potential drug interactions affecting the chiral inversion as well as the formation of hybrid triglycerides with the ( )-enantiomer, the toxicological significance of which has not been established, would be avoided (Brune et al., 1992 Hall and Xiaotao, 1994).
The substance can alter the amount of insulin needed by diabetics. Some experimentation on rats found that nandrolone can boost heart rate acceleration caused by cocaine in other rat work the combination apparently lowered pulse rate. Nandrolone boosts actions of anti-blood clot medicines, putting patients at risk of excessive bleeding.
Side Effects First-dose effect Marked postural hypotension and syncope. CV Palpitations, tachycardia, postural hypotension, syncope, arrhythmias, chest pain, vasodilation. CNS Dizziness, headache, somnolence, drowsiness, nervousness, pares-thesia, depression, anxiety, insomnia, vertigo. Respiratory Nasal congestion, dyspnea, sinusitis, epistaxis, bronchitis, bronchospasm, cold or flu symptoms, increased cough, pharyngitis, rhinitis. Oral Dry mouth. GI Nausea, constipation, diarrhea, dyspepsia, vomiting, flatulence, abdominal discomfort or pain. Musculoskeletal Asthenia, arthritis, arthralgia, myalgia, joint disorders, back pain, pain in extremities, neck and shoulder pain, muscle cramps. Miscellaneous Peripheral edema, weight gain, blurred vision, impotence, chest pain, fever, gout, pruritus, rash, sweating, urinary frequency, UTI, tinnitus, conjunctivitis, abnormal vision, edema, facial edema. Drug Interactions Indomethacin l Effects of terazo-sin
Carbamazepine has been used to treat painful diabetic neuropathy and trigeminal neuralgia (40). Carbamazepine autoinduces its hepatic metabolism, so the practitioner must start at low doses (i.e., 100 mg po twice daily) and increase the dosage weekly to the therapeutic dose (approx 1200 mg po qd, although dosages up to 1600 mg per day have been necessary for pain relief) (38). Carbamazepine is responsible for many drug interactions because of its ability to induce hepatic enzyme activity. Adverse effects include CNS effects (drowsiness, vertigo, ataxia, diplopia, and blurred vision) GI effects (nausea, vomiting) serious hematologic toxicity (aplastic anemia, agranulocytosis) transient increase in hepatic enzymes and hypersensitivity reactions (dermatitis, eosinophilia, lymphadenopathy, splenomegaly) (41). therapeutic concentrations, the rate of metabolism is close to the limit, and small dosage increases may result in significantly higher serum concentrations. Phenytoin is also highly...
Etanercept is a dimeric fusion protein that is indicated for the treatment of RA, juvenile RA, ankylosing spondylitis, psoriatic arthritis, and psoriasis. Drug interaction studies of etanercept have been conducted with several drugs. The summary of these drug-drug interaction studies is as follows. 24 children who received basiliximab reached cyclosporine trough concentrations above 300 mg L, compared with 9 of 15 controls. At days 28 to 50, patients who received basiliximab showed a substantial decline in whole blood concentrations of cyclosporine (21 of 24 patients had
Sue or organ disorders that are disease phenotypes reflected as symptoms of the whole body. In addition, varied genetic structure and altered functions may influence the gene-nutrient and gene-drug interactions, which ultimately affect nutritional or drug-response phenotypes. On the other hand, interactions among genes, foods, drugs, and the environment at higher levels may also affect the structure and function of genes at the molecular level, which would in turn change downstream reactions and phenotypes, forming a feedback loop. The understanding of such interwoven network may be the ultimate key to accurately identifying drug targets and to avoid adverse reactions. In these correlations, genotype-phenotype is the broadest concept that covers the whole biomedical process of drug therapy. However, identification of the other correlations is also important to provide detailed cause-effect relations in this process.
Allopurinol (Zyloprim, Progout) is the only xanthine oxidase inhibitor available in this class. It is rapidly metabolized to its active isomer oxypurinol (Oxyprim), an experimental drug currently in phase III trials, that has a half-life of approximately 15 hours but was found to exhibit a similar side effect profile to that of allopurinol (i.e., 40 of those allergic to allopurinol have similar cross-reactivity to this drug).240 Allopurinol and its active metabolite, oxy-purinol, works by effectively competing with the substrate hypoxanthine and xanthine, respectively, because of their structural similarity to xanthine, for xanthine oxidase, thus blocking uric acid formation from purine nucleosides, adenine, and guanine as shown in Figure 24.25. Similarly, al-lopurinol (or oxypurinol) may also exhibit potential drug interactions with other medications such as didanosine (antiviral agent), azathioprine and mercaptopurine (anticancer drugs), and theophylline (asthma drug). For example,...
Drug interactions Severe interactions have been observed when rifabutin and clarithromycin are given simultaneously (16R). The mean concentrations of rifabutin and 25-O-desacetyl-rifabutin in healthy subjects who took clar-ithromycin and rifabutin concomitantly were respectively more than 4 times and 37 times greater than the concentrations recorded when rifabutin was administered alone. Neutrope-nia was detected in 14 of 18 subjects taking rifabutin. Myalgia and high fever were also common. Physicians should be aware that recommended prophylactic doses of rifabutin can be associated with severe neutropenia within 2 weeks after the start of therapy, and all patients taking rifabutin, especially with clarithromycin, should be monitored carefully for neutropenia.
Possible drug interactions may stem from devil's claw ability to inhibit cytochrome P-450 2C9 (CYP2C9), although the effect has not been reported in humans (Unger and Frank 2004). The pain physician should be advised that drugs metabolized by CYP2C9 such as NSAIDs meloxicam (Mobic) piroxicam (Feldene) celecoxib (Celebrex) amitriptyline (Elavil) warfarin (Coumadin) glipizide (Glucotrol) losartan (Cozaar) and others may need to be reduced or even eliminated.
Use with caution in clients with a history of GI tract disorders, in fluid retention, hypertension, and heart failure. Additional Side Effects GI Peptic ulcer, GI bleeding, dyspepsia, nausea, diarrhea, constipation, abdominal pain, flatulence, anorexia, vomiting, stomatitis. CNS Headache. CV Peripheral edema, fluid retention. Additional Drug Interactions Acetylsalicylic acid T Plasma ketoprofen levels due to l plasma protein binding