{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/31768"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/31768","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"Evaluation of the effects of clomipramine on the canine hypothalamic-pituitary-thyroid axis","abstract":"Tricyclic antidepressants have been shown to alter thyroid function in man and laboratory animals, but have not been evaluated in the dog. The effect of administration of clomipramine on canine thyroid function was studied in a prospective protocol in which 14 mature, healthy dogs were administered clomipramine (3 mg/kg PO q12h) for 112 days. Thyroid-stimulating hormone (TSH), total thyroxine (T4), total 3,5,3' triiodothyronine (T3), free thyroxine (fT4), and 3,3',5' triiodothyronine (reverse T3; rT3) concentrations were measured on selected days. Thyrotropin-releasing hormone (TRH) response tests were performed concurrently. Repeated measures analysis of variance was applied to test for effects of day of treatment; when significance (p < 0.05) was noted, it was further investigated using orthogonal polynomial trends. Significant decreases were found in serum T4 (26 ± 1.2 to 17 ± 0.5 nmol/L, p < 0.001), fT4, (29 ± 2.4 to 19 ± 1.3 pmol/L, p < 0.0002), and rT3 (1.2 ± 0.1 to 0.83 ± 0.08 nmol/L, p < 0.0001) concentrations. The effect of time on serum T3 concentration was also significant (p < 0.0001), but no consistent trend could be identified. No significant effect of time was noted in either pre- or post-TRH TSH concentrations. The results of this study indicate that significant and substantial decreases in T4 (35%), fT4 (38%), and rT3 can occur during clomipramine administration. Long-term administration of clomipramine may result in a misdiagnosis of hypothyroidism if a dog is tested while taking this medication and, since decreased serum fT4 occurs, hypothyroidism may result.","abstract_html":"Tricyclic antidepressants have been shown to alter thyroid function in man and laboratory animals, but have not been evaluated in the dog. The effect of administration of clomipramine on canine thyroid function was studied in a prospective protocol in which 14 mature, healthy dogs were administered clomipramine (3 mg/kg PO q12h) for 112 days. Thyroid-stimulating hormone (TSH), total thyroxine (T4), total 3,5,3&#x27; triiodothyronine (T3), free thyroxine (fT4), and 3,3&#x27;,5&#x27; triiodothyronine (reverse T3; rT3) concentrations were measured on selected days. Thyrotropin-releasing hormone (TRH) response tests were performed concurrently. Repeated measures analysis of variance was applied to test for effects of day of treatment; when significance (p &lt; 0.05) was noted, it was further investigated using orthogonal polynomial trends. Significant decreases were found in serum T4 (26 ± 1.2 to 17 ± 0.5 nmol/L, p &lt; 0.001), fT4, (29 ± 2.4 to 19 ± 1.3 pmol/L, p &lt; 0.0002), and rT3 (1.2 ± 0.1 to 0.83 ± 0.08 nmol/L, p &lt; 0.0001) concentrations. The effect of time on serum T3 concentration was also significant (p &lt; 0.0001), but no consistent trend could be identified. No significant effect of time was noted in either pre- or post-TRH TSH concentrations. The results of this study indicate that significant and substantial decreases in T4 (35%), fT4 (38%), and rT3 can occur during clomipramine administration. Long-term administration of clomipramine may result in a misdiagnosis of hypothyroidism if a dog is tested while taking this medication and, since decreased serum fT4 occurs, hypothyroidism may result.","abstract_has_math":false,"creators":["Gulikers, Keven Peter"],"institution":"Virginia Tech","degree_name":"Master of Science","degree_level":"masters","degree_discipline":"Veterinary Medical Sciences","degree_department":"Veterinary Medical Sciences","school":null,"contributors":[],"advisors":[],"committee_chairs":["Panciera, David L."],"committee_members":["Wilcke, Jeffrey R.","Monroe, William E."],"year":2002,"date_issued":"2002-04-08","date_published":"2002-04-08","updated_at":"2026-07-22T22:19:35Z","subjects":["thyroxine","tricyclic antidepressant","thyroid","hormone","clomipramine","canine"],"languages":[],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-04192002-163244"],"render_values":[{"text":"etd-04192002-163244","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/10919/31768","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.committeechair","label":"Committee Chair","values":["Panciera, David L."]},{"key":"dc:contributor.committeemember","label":"Committee Member","values":["Wilcke, Jeffrey R.","Monroe, William E."]},{"key":"dc:contributor.department","label":"Department","values":["Veterinary Medical Sciences"]},{"key":"dc:creator","label":"Author","values":["Gulikers, Keven Peter"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2014-03-14T20:33:52Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2014-03-14T20:33:52Z","2012-10-01"]},{"key":"dc:date.issued","label":"Date","values":["2002-04-08"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Tech"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Veterinary Medical Sciences"]},{"key":"thesis:degree_level","label":"Degree Level","values":["masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Virginia Polytechnic Institute and State University"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["thyroxine","tricyclic antidepressant","thyroid","hormone","clomipramine","canine"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["In Copyright"]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://rightsstatements.org/vocab/InC/1.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-04192002-163244"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/10919/31768"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Tricyclic antidepressants have been shown to alter thyroid function in man and laboratory animals, but have not been evaluated in the dog. The effect of administration of clomipramine on canine thyroid function was studied in a prospective protocol in which 14 mature, healthy dogs were administered clomipramine (3 mg/kg PO q12h) for 112 days. Thyroid-stimulating hormone (TSH), total thyroxine (T4), total 3,5,3' triiodothyronine (T3), free thyroxine (fT4), and 3,3',5' triiodothyronine (reverse T3; rT3) concentrations were measured on selected days. Thyrotropin-releasing hormone (TRH) response tests were performed concurrently. Repeated measures analysis of variance was applied to test for effects of day of treatment; when significance (p < 0.05) was noted, it was further investigated using orthogonal polynomial trends. Significant decreases were found in serum T4 (26 ± 1.2 to 17 ± 0.5 nmol/L, p < 0.001), fT4, (29 ± 2.4 to 19 ± 1.3 pmol/L, p < 0.0002), and rT3 (1.2 ± 0.1 to 0.83 ± 0.08 nmol/L, p < 0.0001) concentrations. The effect of time on serum T3 concentration was also significant (p < 0.0001), but no consistent trend could be identified. No significant effect of time was noted in either pre- or post-TRH TSH concentrations. The results of this study indicate that significant and substantial decreases in T4 (35%), fT4 (38%), and rT3 can occur during clomipramine administration. Long-term administration of clomipramine may result in a misdiagnosis of hypothyroidism if a dog is tested while taking this medication and, since decreased serum fT4 occurs, hypothyroidism may result."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Master of Science"]},{"key":"dc:title","label":"Title","values":["Evaluation of the effects of clomipramine on the canine hypothalamic-pituitary-thyroid axis"]}]}],"canonical_facts":{"dc:contributor.committeechair":["Panciera, David L."],"dc:contributor.committeemember":["Wilcke, Jeffrey R.","Monroe, William E."],"dc:contributor.department":["Veterinary Medical Sciences"],"dc:creator":["Gulikers, Keven Peter"],"dc:date.accessioned":["2014-03-14T20:33:52Z"],"dc:date.available":["2014-03-14T20:33:52Z","2012-10-01"],"dc:date.issued":["2002-04-08"],"dc:description.abstract":["Tricyclic antidepressants have been shown to alter thyroid function in man and laboratory animals, but have not been evaluated in the dog. The effect of administration of clomipramine on canine thyroid function was studied in a prospective protocol in which 14 mature, healthy dogs were administered clomipramine (3 mg/kg PO q12h) for 112 days. Thyroid-stimulating hormone (TSH), total thyroxine (T4), total 3,5,3' triiodothyronine (T3), free thyroxine (fT4), and 3,3',5' triiodothyronine (reverse T3; rT3) concentrations were measured on selected days. Thyrotropin-releasing hormone (TRH) response tests were performed concurrently. Repeated measures analysis of variance was applied to test for effects of day of treatment; when significance (p < 0.05) was noted, it was further investigated using orthogonal polynomial trends. Significant decreases were found in serum T4 (26 ± 1.2 to 17 ± 0.5 nmol/L, p < 0.001), fT4, (29 ± 2.4 to 19 ± 1.3 pmol/L, p < 0.0002), and rT3 (1.2 ± 0.1 to 0.83 ± 0.08 nmol/L, p < 0.0001) concentrations. The effect of time on serum T3 concentration was also significant (p < 0.0001), but no consistent trend could be identified. No significant effect of time was noted in either pre- or post-TRH TSH concentrations. The results of this study indicate that significant and substantial decreases in T4 (35%), fT4 (38%), and rT3 can occur during clomipramine administration. Long-term administration of clomipramine may result in a misdiagnosis of hypothyroidism if a dog is tested while taking this medication and, since decreased serum fT4 occurs, hypothyroidism may result."],"dc:description.degree":["Master of Science"],"dc:identifier.other":["etd-04192002-163244"],"dc:identifier.uri":["http://hdl.handle.net/10919/31768"],"dc:publisher":["Virginia Tech"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:subject":["thyroxine","tricyclic antidepressant","thyroid","hormone","clomipramine","canine"],"dc:title":["Evaluation of the effects of clomipramine on the canine hypothalamic-pituitary-thyroid axis"],"dc:type":["Thesis"],"thesis:degree_discipline":["Veterinary Medical Sciences"],"thesis:degree_level":["masters"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["Virginia Polytechnic Institute and State University"]},"updated_at":"2026-07-22T22:19:35Z"}