Surgery services

  • Hyperthyroidism (e.g. graves disease)
  • Hypothyroidism (e.g. Hashimotothyreoiditis)
  • Enlarged thyroid or goiter
  • Thyroid cancer and thyroid tumor inclusive aftercare and follow up
  • Hyperparathyroidism
  • Thyroid ultrasound
  • Ultrasound guided needle biopsy of thyroid nodules
  • Consultation and treatment for
    • Diabetes type 1 and type 2
    • Gestational diabetes
    • and other forms
  • Differential diagnosis and treatment of diabetic specific complications, e.g. diabetic foot syndrome
  • Use of insulin pumps and blood sugar monitors (continuous glucose monitoring, CGM and flash glucose measurements, glucose sensor implantion)
  • Differential diagnosis of symptoms of possible hormonal imbalance, e.g. fatigue, increased perspiration, hair loss, increased body hair in women, reduced libido, breast swelling in men, hypertension, dwarfism and gigantism, infertility, abnormal menstruation, menopause complaints, increased thirst
  • Differential diagnosis and treatment of testerone deficiency
  • Differential diagnosis and treatment of pituitary and adrenal disorders (Hyper- and hypofunction)
  • Differential diagnosis and treatment of osteoporosis
  • Differential diagnosis and treatment of male and female gonadal disorders
  • Hormone therapy for transgender
  • Differential diagnosis and treatment of lipid metabolism disorders (e.g. familial hypercholesterolemia)
  • Differential diagnosis of causes of overweight and obesity
  • Weight loss consultation and support
  • Preparation for and follow-up to weight loss surgery (bariatric surgery e.g. gastric bypass surgery or stomach sleeve)


  • Haemogram, blood sedimentation
  • Inflammation protein
  • Urin test strip
  • Blood sodium levels (sodium, chloride, calcium, magnesium, phosphate)
  • Kidney function (creatinine, urea)
  • Protein (albumen)
  • Cholesterol values (total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides)
  • Blood sugar (glucose)
  • HbA1c
  • Liver function
  • Uric acid
  • Thyroid hormone (TSH, T4, T3)
  • Gestational hormon (Beta HCG)
  • Heart failure marker (pro-BNP)
  • Testosterone, oestrogen, androstenedione, DHEAS, luteinizing hormones (LH, FSH)
  • Bone metabolism: vitamin D, parathormone, calcitonin
  • Bone remodelling markers: alkaline phosphatase, P1NP, CTx
  • Thyroid hormones: TSH, fT3, fT4
  • Stress hormones (adrenaline, noradrenaline, dopamine) and stress hormone metabolites (catecholamines)
  • Adrenals: aldosterone, cortisol
  • urin free cortisol (VFC)
  • Late-night salivary cortisol
  • et cetera
  • Clonidine test: examination of growth hormone or stress hormone levels
  • Low-Dose-Synacthent test: examination of adrenal gland (cortisol)
  • TRH test: examination of the pituitary gland for thyroid
  • Glucose tolerance test: on suspicion of diabetes mellitus, gestational diabetes, growth hormone excess
  • Insulin hypoglycemia test: examination of the pituitary gland for growth hormone and cortisol
  • GHRH-Arginine test: examination of growth hormone levels
  • 1mg overnight dexamethasone suppression test (DST)
  • Sodium infusion test
  • et cetera
  • Thyroid ultrasound exam with fine needle aspiration biopsy
  • Abdominal sonographie
  • Resting electrocardiogram (ECG), exercise testing by bicycle
  • Pulmonary function tests
  • 24-hour ambulatory blood pressure monitoring
  • Ankel brachial index
  • Sleep apnea screening (OSAS, ApneaLink)
  • All insulin pumps
  • Reading of all types of glucose meters by electronic display
  • Continuous glucose monitoring by sensors over several days


  • Excessive hair or hair loss
  • Fatigue, exhaustion, decreased productivity
  • Increased or reduced thirst
  • Irregular menstrual cycle or absent menstruation
  • Infertility
  • Breast swelling in men
  • Loss of libido, erectile dysfunction
  • Osteoporosis
  • Impaired vision, reduced field of vision, headache
  • Perspiration
  • Panic attacks, trembling
  • Low blood sugar or high blood sugar
  • Constipation or diarrhoea
  • Underweight or overweight
  • Low or high blood pressure
  • Dwarfism or giantism



Med. PA

Dr. med. univ. Arthur Knapp

Chess, Aviation (PPL), Mountaineering, Golf

Married to Nicola, 3 sons (Constantin, Aurel, Ruben).

Professional experience

2022 Chief executive officer - Endokrinologie Rheintal
2016 - 2021 Owner - Praxis für Schilddrüse, Hormone und Diabetes
2015 - 2016 Consultant in Endocrinology/Diabetology, eSwiss/Klinik Stephanshorn, St. Gallen
2014 - 2015 Fellow Endocrinology/Diabetology, Kantonsspital St. Gallen
2012 - 2013 Fellow Endokrinologie/Diabetologie, Fremantle Hospital, University of Western Australia
2010 - 2012 Fellow Endocrinology/Diabetology, Institut DiaMon, Baden-Dättwil
2007 - 2010 Resident in Internal Medicine, Regional hospital Laufenburg, (Aargau) and Kantonsspital Olten
2007 Consultant in General Medicine, State hospital Bludenz, Austria
2004 - 2007 Resident in General Medicine, State hospital Bludenz, Feldkirch, Rankweil, Austria
2003 Dissertation University of Innsbruck, Austria
1995 - 2003 Medical School (Dr. med. univ.), University of Innsbruck, Austria

Board certification

2007 General practitioner (Austria, Switzerland)
2010 Specialist in Internal Medicine (Switzerland)
2015 Endocinology/Diabetology (Switzerland)


  • Advanced training in ultrasound (SGUM)
  • Advanced training in thyroid ultrasound (SGED-SSED)
  • Advance training in practice laboratory (FAPL-KHM)
  • Emergency doctor (ÖAK)
  • Diploma in mountain medicine


  • German
  • English


  • Swiss Society Endocrinology/Diabetology (SGED)
  • Australian Diabetes Society (ads)
  • Endocrine Society
  • European Society of Endocrinology (ECE)
  • Swiss Doctor's society (FMH)
  • Doctor's society Kanton St. Gallen
  • Doctor's society Rorschach-Rheintal (ÄRR)


Office hours:

Monday until Freiday::   07:30 - 12:00 Uhr
  13:00 - 17:30 Uhr

Patient parking spaces are available in front of the medical practice.

Endokrinologie - Diabetologie Rheintal AG

Rorschacherstrasse 1
9450 Altstätten

tel: 071 552 07 40
fax: 071 552 07 49