Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0012833 (dizziness)
 9,689 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The pharmacokinetic and clinical characteristics of a once-daily formulation of diltiazem are described. In a 20 subject, 5 day, steady-state pharmacokinetic study, 120 and 240 mg of once-daily diltiazem were bioequivalent on a dose-adjusted basis and were bioequivalent to a conventional reference product administered four times daily. The conventional formulation showed marked diurnal variation in its pharmacokinetics. Plasma concentrations following its administration at 2100 and 0300 h were significantly lower than following administration at 0900 and 1500 h. One hundred forty-four hypertensive patients completed a 16 week placebo-controlled, dose-titrated study examining the effects of once-daily diltiazem at doses of 120, 240, and 360 mg. Blood pressure was measured manually and (in 121 patients) by ambulatory evaluation. Following dose titration, diltiazem given once daily reduced blood pressure with significant effects present at 24 h following drug administration. Ambulatory blood pressures were lower than those measured manually and data from the manual measurements demonstrated a placebo effect suggested to result primarily from investigator bias. The placebo-adjusted reduction in blood pressure 24 h following a dose of diltiazem was approximately 5 mm Hg and was comparable for manual (supine and standing) and ambulatory measurements. Diltiazem was well tolerated. The only significant findings were of tiredness/dizziness (9 patients of 144) or oedema (also 9 of 144). The incidence of headache was not different than placebo. On both pharmacokinetic and pharmacodynamic grounds, the results indicate that diltiazem can be formulated in a manner suitable for once-daily antihypertensive use.
 ...
PMID:Pharmacokinetic properties and antihypertensive efficacy of once-daily diltiazem. 171 21

The pharmacokinetics, clinical efficacy, and adverse effects of three calcium-channel blocking agents--verapamil, nifedipine, and diltiazem--are reviewed. Verapamil, nifedipine, and diltiazem are absorbed well after oral dosing, but absolute bioavailability of each is reduced substantially by a first-pass effect. Each drug is metabolized extensively (verapamil and diltiazem to moderately active metabolites) by the liver. A substantial percentage of each drug is bound to plasma proteins, but the binding is of clinical importance only for nifedipine (92--98% protein bound). Intravenous verapamil has become the agent of first choice for treatment of acute paroxysmal supraventricular tachycardia (PSVT); use of chronic oral verapamil therapy for prophylaxis remains controversial. Verapamil and diltiazem have been evaluated with mixed results for atrial flutter and fibrillation. For treatment of myocardial ischemia, calcium-channel blockers may be of some value (possibly in combination with nitrates of B blockers). All three agents have been studied in patients with exertional angina with good results. Calcium-channel blockers appear to be equal with nitrates for treatment of variant angina. Patients with hypertropic cardiomyopathy have been treated with verapamil and nifedipine with promising results. Nifedipine has been effective for treatment of essential hypertension. Adverse effects of calcium-channel blockers have been relatively minor or infrequent. Diltiazem overall has the best side-effect profile, with adverse effects causing discontinuation of therapy in about 2--10% of patients; verapamil in intermediate (8--10%) and nifedipine the worst (17%) in this respect. The most common side effects generally are fatigue, headache, dizziness, skin rash, and peripheral edema. While they generally should be reserved for patients in whom more conventional therapy has failed (except those with PSVT), calcium-channel blockers appear to have a valid role as reserve agents for exertional and variant angina, cardiomyopathy, and hypertension.
 ...
PMID:Update on calcium-channel blocking agents. 635 66

Diltiazem HCl was administered p.o. at a fixed daily dose level of 180 mg to patients with essential hypertension, and the hypotensive effect of the drug was investigated. The following results were obtained: diltiazem HCl given alone exhibited a hypotensive effect on systolic pressure in 88.9% of the patients and on diastolic pressure in 66.7% of the patients. The concurrent use of diltiazem HCl with trichlormethiazide exerted a hypotensive effect on patients who were nonresponsive to diltiazem HCl alone. As regards side effects, one patient complained of gastric fullness and one of dizziness. However, the symptoms were so mild that further continuation of diltiazem HCl therapy was possible. From the results obtained, it is concluded that diltiazem HCl can effectively be used clinically as a hypotensive drug.
 ...
PMID:Clinical study on the hypotensive effect of diltiazem hydrochloride. 721 50

Diltiazem is a calcium-channel blocker commonly used for the treatment of hypertension. Common adverse effects include dizziness, headache, and edema. Fewer than 20 cases of diltiazem-associated photodistributed hyperpigmentation have been reported in the literature. Here, we present the case of a 71-year-old woman with new-onset facial hyperpigmentation 6 months after initiating treatment with diltiazem.
 ...
PMID:Diltiazem-associated Photodistributed Hyperpigmentation. 3222 35