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Photodiagnosis and Photodynamic Therapy Jun 2022Erythropoietic protoporphyria (EPP) is caused by deficiency of the enzyme converting protoporphyrin IX (PpIX) into heme resulting in accumulation of PpIX; leading to... (Review)
Review
BACKGROUND
Erythropoietic protoporphyria (EPP) is caused by deficiency of the enzyme converting protoporphyrin IX (PpIX) into heme resulting in accumulation of PpIX; leading to photosensitivity and liver toxicity. Cimetidine might inhibit δ-aminolevulinic acid synthase influencing the heme biosynthesis. We present cases with EPP treated with cimetidine at our department, and a literature review.
METHODS
Systematic searches were performed to identify literature describing EPP patients treated with cimetidine. On that ground we treated EPP patients with cimetidine through spring and summer in 2020 and 2021 at our department. Their erythrocyte PpIX level and standard blood and liver parameters were collected before and during 4 months of treatment. Using a questionnaire, patients were asked about change in photosensitivity, side effects, and whether they would like to resume treatment in the spring of 2022.
RESULTS
Literature searches identified 9 patients treated with cimetidine. Four were outpatients reporting decreased photosensitivity. At our department 18 outpatients started treatment. Fifteen used oral cimetidine daily for 4 months or more providing a significant decrease in erythrocyte PpIX with a median of 20% (range: -18% to 53%) after 4 months. Eleven of the 15 patients reported a decrease in photosensitivity during treatment, 3 patients were unsure, and 1 patient experienced unchanged photosensitivity. Only mild side effects were reported. Fourteen patients requested to resume treatment in the spring of 2022.
CONCLUSIONS
These cases suggest that cimetidine can lower erythrocyte PpIX in patients with EPP.
Topics: Cimetidine; Ferrochelatase; Heme; Humans; Photochemotherapy; Photosensitivity Disorders; Protoporphyria, Erythropoietic; Protoporphyrins
PubMed: 35245673
DOI: 10.1016/j.pdpdt.2022.102793 -
British Medical Journal Jun 1978
Topics: Chronic Disease; Cimetidine; Duodenal Ulcer; Guanidines; Humans; Time Factors
PubMed: 647322
DOI: 10.1136/bmj.1.6125.1435 -
BMJ Clinical Evidence Sep 2009Warts are caused by the human papillomavirus (HPV), of which there are over 100 types, which probably infects the skin via areas of minimal trauma. Risk factors include... (Review)
Review
INTRODUCTION
Warts are caused by the human papillomavirus (HPV), of which there are over 100 types, which probably infects the skin via areas of minimal trauma. Risk factors include use of communal showers, occupational handling of meat, and immunosuppression. In immunocompetent people, warts are harmless and resolve as a result of natural immunity within months or years.
METHODS AND OUTCOMES
We conducted a systematic review and aimed to answer the following clinical question: What are the effects of treatments for warts (non-genital)? We searched: Medline, Embase, The Cochrane Library, and other important databases up to June 2008 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).
RESULTS
We found 12 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.
CONCLUSIONS
In this systematic, review we present information relating to the effectiveness and safety of the following interventions: intralesional bleomycin; cimetidine; contact immunotherapy; cryotherapy; duct tape occlusion; formaldehyde, glutaraldehyde; homeopathy; photodynamic treatment; pulsed dye laser; surgical procedures; topical salicylic acid; and zinc sulphate.
Topics: Administration, Oral; Bandages; Bleomycin; Cimetidine; Cryosurgery; Cryotherapy; Humans; Warts; Zinc Sulfate
PubMed: 21726478
DOI: No ID Found -
Asian Pacific Journal of Cancer... Jun 2022Cimetidine and ibuprofen exhibit immunomodulatory effects as an antagonist of histamine H2 receptor, and a cyclooxygenase inhibitor, respectively. Here, the effects of...
Cimetidine and ibuprofen exhibit immunomodulatory effects as an antagonist of histamine H2 receptor, and a cyclooxygenase inhibitor, respectively. Here, the effects of cimetidine and ibuprofen on some effector T cell-related parameters were investigated using a breast cancer (BC) model. BC was established in Balb/c mice using the 4T1 cell line. On day 10 after tumor induction, the BC-bearing mice were classified into four groups and treated with PBS, cimetidine (20 mg/kg), ibuprofen (20 mg/kg) or a combination of "cimetidine + ibuprofen" via intraperitoneal injection (daily from days 11 to 30). The mice were sacrificed on day 31 and the frequency of splenic Th1 and Treg cells, plasma IFN-γ and TGF-β levels, and intra-tumoral T-bet, GATA3, FOXP3 and RORγt expressions were detected using flowcytometry, ELISA and real-time-PCR, respectively. In untreated cancerous mice, the percentage of splenic Th1 cells and plasma IFN-γ levels were lower (P<0.003 and P<0.01, respectively), whereas the percentage of splenic Treg cells and plasma TGF-β levels were higher than in healthy mice (P<0.04 and P<0.005, respectively). Treatment of BC-bearing mice with cimetidine, ibuprofen or both drugs promoted the frequency of Th1 cells (P<0.05, P<0.007 and P<0.005, respectively) as well as IFN-γ levels (P<0.004, P<0.0001 and P<0.03, respectively), while reduced the frequencies of Treg cells (P<0.02, P<0.03 and P<0.01, respectively), TGF-β levels (P<0.006, P<0.02 and P<0.002, respectively), intra-tumoral expression of FOXP3 (P<0.006, P<0.005 and P<0.005, respectively), and intra-tumoral expression of RORγt (P<0.04, P<0.03 and P<0.05, respectively) compared with untreated BC mice. The "cimetidine + ibuprofen"-treated mice displayed greater T-bet expression than the un-treated mice (P<0.006). Cimetidine and/or ibuprofen-treated BC-bearing mice exhibited reduced intra-tumoral expression of GATA3 compared with the untreated BC mice, but the differences were not significant. Cimetidine and ibuprofen correct some effector T cell-related parameters in cancerous mice. Immunotherapeutic potentials cimetidine and ibuprofen in cancers need investigations.
Topics: Animals; Cimetidine; Disease Models, Animal; Forkhead Transcription Factors; Ibuprofen; Mice; Mice, Inbred BALB C; Neoplasms; Nuclear Receptor Subfamily 1, Group F, Member 3; T-Lymphocytes, Regulatory; Transforming Growth Factor beta
PubMed: 35763623
DOI: 10.31557/APJCP.2022.23.6.1847 -
IARC Monographs on the Evaluation of... 1990
Review
Topics: Animals; Carcinogens; Cimetidine; Dogs; Female; Male; Mice; Molecular Structure; Pregnancy; Rats; Reproduction
PubMed: 2292801
DOI: No ID Found -
Journal of Anatomy Jul 2021Submandibular gland (SMG) is responsive to androgens via androgen receptor (AR). We verified whether cimetidine induces androgenic dysfunction in SMG, and evaluated the...
Submandibular gland (SMG) is responsive to androgens via androgen receptor (AR). We verified whether cimetidine induces androgenic dysfunction in SMG, and evaluated the structural integrity, cell death and immunoexpression of actin, EGF and V-ATPase in androgen-deficient SMG. Male rats received cimetidine (CMTG) and control animals (CG) received saline. Granular convoluted tubules (GCTs) diameter and number of acinar cell nuclei were evaluated. TUNEL and immunofluorescence reactions for detection of AR, testosterone, actin, EGF and V-ATPase were quantitatively analysed. In CG, testosterone immunolabelling was detected in acinar and ductal cells cytoplasm. AR-immunolabelled nuclei were observed in acinar cells whereas ductal cells showed AR-immunostained cytoplasm, indicating a non-genomic AR action. In CMTG, the weak testosterone and AR immunoexpression confirmed cimetidine-induced androgenic failure. A high cell death index was correlated with decreased number of acinar cells, GCTs diameter and EGF immunoexpression under androgenic dysfunction. Actin immunofluorescence decreased in the SMG cells, but an increased and diffuse cytoplasmic V-ATPase immunolabelling was observed in striated ducts, suggesting a disruption in the actin-dependent V-ATPase recycling due to androgenic failure. Our findings reinforce the androgenic role in the maintenance of SMG histophysiology, and point to a potential clinical use of cimetidine against androgen-dependent glandular tumour cells.
Topics: Actins; Animals; Cimetidine; Cytochrome P-450 CYP1A2 Inhibitors; Drug Evaluation, Preclinical; Epidermal Growth Factor; Male; Rats, Sprague-Dawley; Receptors, Androgen; Submandibular Gland; Testosterone; Vacuolar Proton-Translocating ATPases; Rats
PubMed: 33713423
DOI: 10.1111/joa.13408 -
The Cochrane Database of Systematic... Mar 2012Urticaria is a common skin disease characterised by itching weals or hives, which can occur almost anywhere on the body. There are a number of different subtypes and a... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Urticaria is a common skin disease characterised by itching weals or hives, which can occur almost anywhere on the body. There are a number of different subtypes and a range of available treatment options. There is lack of agreement on the efficacy of H2-receptor antagonists used in the treatment of urticaria.
OBJECTIVES
To assess the safety and effectiveness of H2-receptor antagonists in the treatment of urticaria.
SEARCH METHODS
We searched the following databases up to 7 October 2011: the Cochrane Skin Group Specialised Register, CENTRAL in The Cochrane Library (2011, Issue 4), MEDLINE (from 2005), EMBASE (from 2007), and LILACS (from 1982). We also searched online trials registries for ongoing trials.
SELECTION CRITERIA
Randomised controlled trials of H2-receptor antagonists in people with a clinical diagnosis of urticaria of any duration or of any subtype. Studies including H1-antihistamines for chronic urticaria are the topic of a separate Cochrane review; thus, they were not included in this review.
DATA COLLECTION AND ANALYSIS
Two reviewers independently assessed trial quality and extracted and analysed data.
MAIN RESULTS
Four studies of a relatively small size, involving 144 participants, were included in this review. A combination of ranitidine with diphenhydramine was more effective at improving the resolution of urticaria than diphenhydramine administered alone (risk ratio (RR) 1.59, 95% confidence interval (CI) 1.07 to 2.36). Although there was a similar improvement in itching, weal size, and intensity, cimetidine provided no statistically significant greater overall improvement in symptoms of urticaria when compared to diphenhydramine. However, a combination of these medications was more effective than diphenhydramine alone (RR 2.02, 95% CI 1.03 to 3.94). Adverse events were reported with several of the interventions, i.e. ranitidine and diphenhydramine, causing drowsiness and sedation, but there was no significant difference in the level of sedation from baseline with either famotidine or diphenhydramine.
AUTHORS' CONCLUSIONS
The very limited evidence provided by this review was based on a few old studies of a relatively small size, which we categorised as having high to unclear risk of bias. Thus, at present, the review does not allow confident decision-making about the use of H2-receptor antagonists for urticaria. Although some of these studies have reported a measure of relief of symptoms of urticaria and rather minimal clinical improvement in some of the participants, the evidence was weak and unreliable. We have emphasised the lack of precision and limitations in the reported data where appropriate in this review.
Topics: Cimetidine; Diphenhydramine; Drug Therapy, Combination; Famotidine; Histamine H1 Antagonists; Histamine H2 Antagonists; Humans; Randomized Controlled Trials as Topic; Ranitidine; Urticaria
PubMed: 22419335
DOI: 10.1002/14651858.CD008596.pub2 -
Clinical Pharmacology and Therapeutics Jul 2020The US Food and Drug Administration (FDA) lists 22 medications as clinical inhibitors of cytochrome P450 2D6 isoenzyme, with classifications of strong, moderate, and... (Review)
Review
The US Food and Drug Administration (FDA) lists 22 medications as clinical inhibitors of cytochrome P450 2D6 isoenzyme, with classifications of strong, moderate, and weak. It is accepted that strong inhibitors result in nearly null enzymatic activity, but reduction caused by moderate and weak inhibitors is less well characterized. The objective was to identify if the classification of currently listed FDA moderate and weak inhibitors is supported by publicly available primary literature. We conducted a literature search and reviewed product labels for area under the plasma concentration-time curve (AUC) fold-changes caused by inhibitors in humans and identified 89 inhibitor-substrate pairs. Observed AUC fold-change of the substrate was used to create an observed inhibitor classification per FDA-defined AUC fold-change thresholds. We then compared the observed inhibitor classification with the classification listed in the FDA Table of Inhibitors. We found 62% of the inhibitors within the pairs matched the listed FDA classification. We explored reasons for discordance and suggest modifications to the FDA table of clinical inhibitors for cimetidine, desvenlafaxine, and fluvoxamine.
Topics: Area Under Curve; Cimetidine; Cytochrome P-450 CYP2D6; Cytochrome P-450 CYP2D6 Inhibitors; Desvenlafaxine Succinate; Fluvoxamine; Humans
PubMed: 31910286
DOI: 10.1002/cpt.1768 -
Journal of Cancer Research and... 2021The study aims at evaluating the effects of the combinatory famotidine/cimetidine diet on radiated mice's survival.
AIMS
The study aims at evaluating the effects of the combinatory famotidine/cimetidine diet on radiated mice's survival.
MATERIALS AND METHODS
Two hundred and seventy male mice were categorized into 11 groups, a number of which were comprised of subgroups too. The groups under analysis were posed to varying doses of gamma-radiation, including 6, 7, 8, and 9 Gy, followed by treatments using various drug doses 2, 4, and 8 mg/kg, with survival fractions as long as a month after irradiation being measured and recorded.
RESULTS
LD was calculated as 7.47 Gy for the group with radiation only. Following mouse treatment with a concentration of 4 and 20 mg/kg for famotidine and cimetidine, respectively, the survival fraction for the mice grew significantly compared to LD. The combinatory famotidine/cimetidine diet had a higher dose-reduction factor (DRF) than single doses of the drug in radioprotection. The DRF for combinatory famotidine/cimetidine, famotidine, and cimetidine diets was 08.09, 1.1, and 1.01, respectively.
CONCLUSIONS
Results imply that the combined regimen of famotidine + cimetidine in radioprotection had no significant higher DRF than with regimens including each of them separately. In addition, we did not find a synergic effect of combined oral famotidine and cimetidine on irradiated mice.
Topics: Administration, Oral; Animals; Cimetidine; Drug Therapy, Combination; Famotidine; Histamine H2 Antagonists; Male; Mice; Radiation Injuries; Survival Rate; Whole-Body Irradiation
PubMed: 34528533
DOI: 10.4103/jcrt.JCRT_349_19 -
Clinical Pharmacokinetics Nov 2020Metformin is a widely prescribed antidiabetic BCS Class III drug (low permeability) that depends on active transport for its absorption and disposition. It is...
A Comprehensive Whole-Body Physiologically Based Pharmacokinetic Drug-Drug-Gene Interaction Model of Metformin and Cimetidine in Healthy Adults and Renally Impaired Individuals.
BACKGROUND
Metformin is a widely prescribed antidiabetic BCS Class III drug (low permeability) that depends on active transport for its absorption and disposition. It is recommended by the US Food and Drug Administration as a clinical substrate of organic cation transporter 2/multidrug and toxin extrusion protein for drug-drug interaction studies. Cimetidine is a potent organic cation transporter 2/multidrug and toxin extrusion protein inhibitor.
OBJECTIVE
The objective of this study was to provide mechanistic whole-body physiologically based pharmacokinetic models of metformin and cimetidine, built and evaluated to describe the metformin-SLC22A2 808G>T drug-gene interaction, the cimetidine-metformin drug-drug interaction, and the impact of renal impairment on metformin exposure.
METHODS
Physiologically based pharmacokinetic models were developed in PK-Sim (version 8.0). Thirty-nine clinical studies (dosing range 0.001-2550 mg), providing metformin plasma and urine data, positron emission tomography measurements of tissue concentrations, studies in organic cation transporter 2 polymorphic volunteers, drug-drug interaction studies with cimetidine, and data from patients in different stages of chronic kidney disease, were used to develop the metformin model. Twenty-seven clinical studies (dosing range 100-800 mg), reporting cimetidine plasma and urine concentrations, were used for the cimetidine model development.
RESULTS
The established physiologically based pharmacokinetic models adequately describe the available clinical data, including the investigated drug-gene interaction, drug-drug interaction, and drug-drug-gene interaction studies, as well as the metformin exposure during renal impairment. All modeled drug-drug interaction area under the curve and maximum concentration ratios are within 1.5-fold of the observed ratios. The clinical data of renally impaired patients shows the expected increase in metformin exposure with declining kidney function, but also indicates counter-regulatory mechanisms in severe renal disease; these mechanisms were implemented into the model based on findings in preclinical species.
CONCLUSIONS
Whole-body physiologically based pharmacokinetic models of metformin and cimetidine were built and qualified for the prediction of metformin pharmacokinetics during drug-gene interaction, drug-drug interaction, and different stages of renal disease. The model files will be freely available in the Open Systems Pharmacology model repository. Current guidelines for metformin treatment of renally impaired patients should be reviewed to avoid overdosing in CKD3 and to allow metformin therapy of CKD4 patients.
Topics: Adult; Cimetidine; Drug Interactions; Humans; Hypoglycemic Agents; Metformin; Pharmacogenetics; Renal Insufficiency, Chronic
PubMed: 32449077
DOI: 10.1007/s40262-020-00896-w