Drug & nutrient interactions Flashcards
What type of drugs may cause weight gain/appetite stimulation?
- psychotropic medicines (anti-psychotic or anti-depressants)
- anti-histamines
- insulin and oral hypoglycemics
- corticosteroids (asthma)
It is thought that anti-psychotic drugs may contribute to an increased risk of diabetes, why?
Potentially due to the associated weight gain (30% weight gain with Olanzapine)
What side effects do some drugs cause that may lead to loss of appetite?
- gastric upset (chemotherapy drugs inducing nausea and vomiting, or opioids)
- dry mouth
- swallowing difficulties
- taste/smell changes
How do amphetamines result in weight loss?
Cause appetite suppression - however potential for addiction and may only have a short term effect due to tolerance
Name an example of a weight loss drug?
Orlistat
How does Orlistat contribute to weight loss?
It inhibits Lipase activity in the small intestine, leading to enhanced dietary triglyceride excretion in the faeces, and consequent reduced fat absorption
(lipase is usually secreted to help breakdown fat for absorption)
What side effects may orlistat cause?
Bloating and oily stools
What drugs act on bile acids to help reduce cholesterol?
Ezetimibe, plant sterols, and bile acid binding resins
How do ezetimibe, plant sterols and bile acid binding resins lower cholesterol?
They bind to bile acids to stop reuptake by the liver, therefore cause the liver to use cholesterol to make more therefore depleting the cholesterol pool
What is the overall role of ezetimibe, plant sterols, and bile acid binding resins?
Lower cholesterol
What is the overall role of statins?
Lower cholesterol
How do statins lower cholesterol?
They inhibit HMG Co-A reductase to inhibit cholesterol production
They also increase LDL receptos on liver to help pull LDL out of the blood, and therefore decrease the cholesterol pool
What are the cons of bile acid binding resins?
- need to be taken with every meal
- powder to mix with drink
- can cause GI upset
- drug-drug interactions
What are 3 therapeutic approaches to managing diabetes?
- direct administration of insulin
- stimulate B cells of pancreas to stimulate release of insulin
- alter glucose absorption, production, utilisation and excretion
Why can’t insulin be given orally?
It is a peptide and too large to be absorbed in GIT and needs to get into the blood
How do rapid acting insulins work?
They are in monomoer form and therefore can rapidly diffuse - reduce BGL at mealtimes
How do longer acting insulins work?
They are aggregated in hexamer form which means they are less quickly absorbed due to limited diffusion - manage the body’s general insulin needs
What are causes of hypoglycemia?
- delay in a meal
- inadequate CHO consumption
- excess insulin dose
What are the symptoms of hypoglycemia?
Adrenaline effects - early: tachycardia, tremor, sweating
neuroglycopenia - mental function/consciousness
What is the role of a SGLT2 inhibitor?
Inhibits SGLT2 and stops reabsorption of glucose in the kidneys, therefore excretes glucose in urine
How can SGLT2 inhibitors cause weight loss?
- decreases calorie usage by excreting glucose
- excess water excretion
What are adverse effects of SGLT2 inhibitors?
- genital and urinary tract infections
- polyuria