chapter 53 lehne

Cholestyramine

A medication that binds bile acids in the intestine, preventing their reabsorption and lowering LDL cholesterol levels.

Administration Instructions for cholestryramine

Mix powder form with fluids before taking.

Suitable mixing options for Cholestyramine

Water, fruit juices, soups, pulpy fruits (applesauce, crushed pineapple).

Timing Considerations for Cholestyramine

Check for drug interactions with other medications; may need to space timing between other medications; take as prescribed (dosage range 4-24g/day).

Side Effects to Monitor for Cholestyramine

Constipation, abdominal discomfort, bloating, nausea, vomiting, diarrhea, skin reactions.

Important Reminders for Cholestyramine

Mix thoroughly with liquid before taking; maintain adequate fluid intake; report severe gastrointestinal symptoms; follow prescribed dosing schedule; store medication properly; keep regular follow-up appointments.

Special Considerations for Cholestyramine

May affect absorption of fat-soluble vitamins; report any new medications to healthcare provider; continue medication unless told to stop by provider.

Mechanism of Action of Cholestyramine

Binds bile acids in intestine, prevents reabsorption, increases bile acid excretion through feces, and lowers LDL cholesterol levels.

How Cholestyramine Works

Forms insoluble complex with bile acids, forcing liver to increase bile acid production, which requires more cholesterol and increases LDL receptors, resulting in decreased LDL cholesterol levels.

Clinical Effects of Cholestyramine

Reduces LDL cholesterol by about 20%; effects begin within first week; maximum effect reached in about one month; can help relieve itching in jaundiced patients; may temporarily increase VLDL levels.

Key Characteristics of Cholestyramine

Biologically inert, not absorbed by body, passes through GI tract unchanged, excreted in feces.

Cholesterol Return to Baseline

Takes 3-4 weeks for cholesterol to return to baseline after stopping Cholestyramine.

Statin

A class of drugs used to lower cholesterol levels in the blood.

Pregnancy Considerations for Statins

Contraindicated during pregnancy; women of childbearing age must avoid pregnancy; discontinue if pregnancy occurs.

Myopathy Risk Management for Statins

Report unexplained muscle pain/tenderness; monitor for muscle weakness; seek immediate medical attention if severe muscle symptoms occur; watch for drug interactions with Gemfibrozil, Fenofibrate, Macrolide antibiotics, Antifungal medications, HIV protease inhibitors.

Adherence Strategies for Statins

Use pill organizers; take medication as prescribed; maintain regular schedule; do not stop without medical advice; keep all follow-up appointments.

Important Monitoring for Statins

Baseline CK levels; thyroid function if muscle pain develops; regular liver function tests; vitamin D levels; Coenzyme Q levels.

Patient Understanding for Statins

Long-term therapy required; benefits outweigh risks; regular monitoring necessary; lifestyle modifications important; report all new medications to healthcare provider.

Bile Acid Sequestrants and Diabetes

The connection between bile acid sequestrants and diabetes isn't directly addressed; these medications work by binding to bile acids in the intestine and preventing their reabsorption.

LDL receptor activity

Increases LDL receptor activity in liver cells.

LDL cholesterol reduction

Reduces LDL cholesterol levels by about 20% within a month.

VLDL levels

May temporarily increase VLDL levels.

Bile acid sequestrants

Medications that are biologically inert, cannot be absorbed from the GI tract, and are excreted unchanged in feces.

Colestipol

A bile acid sequestrant used to lower cholesterol.

Colesevelam

A newer, better tolerated bile acid sequestrant option.

Initial effects of statins

Significant LDL reduction within 2 weeks.

Maximum effect of statins

Maximum effect achieved in 4-6 weeks.

Statin administration timing

Most effective when administered in evening hours.

Duration of statin effects

Effects last as long as medication is continued.

Cholesterol return after stopping statins

If therapy stops, cholesterol returns to pre-treatment levels within weeks to months.

Oral absorption of statins

Varies (30-90% depending on specific statin).

Liver processing of statins

Most of absorbed dose is processed by liver on first pass.

Systemic circulation of statins

Small fraction reaches systemic circulation.

Hepatic metabolism of statins

Rapid hepatic metabolism.

Statin excretion

Primary excretion through bile; select statins have 10-20% urinary excretion.

Asian patients and rosuvastatin

Asian patients taking rosuvastatin may show twice the blood levels compared to Caucasian patients.

LDL's role in atherosclerosis

Delivers cholesterol to tissues and high serum LDL strongly indicates coronary risk.

Oxidized LDL

Excess LDL migrates into vessel walls, undergoes oxidation, and is phagocytized by macrophages.

HDL's protective functions

Performs 'reverse cholesterol transport' and aids in endothelial repair.

Disease progression in atherosclerosis

Initial endothelial injury, formation of fatty streak, development of fibrotic plaque, evolution to complicated lesion.

Major adverse effects of statins

Myopathy/Rhabdomyolysis occurs in 5-10% of patients.

Symptoms of myopathy

Muscle aches, tenderness, weakness.

CK monitoring

Stop statin if CK >10x upper limit normal; weekly monitoring if CK <10x ULN.

Hepatotoxicity in statins

Affects 0.5-2% of patients on long-term therapy.

Required laboratory analysis for statins

Baseline CK levels, baseline LFTs, thyroid function if muscle pain develops.