How does Triquilar (ethinyl estradiol and levonorgestrel) affect lipid profiles?

Effects of Triquilar (Ethinyl Estradiol and Levonorgestrel) on Lipid Profiles

Triquilar, a triphasic oral contraceptive containing ethinyl estradiol and levonorgestrel, typically causes moderate increases in triglyceride levels (20-30% on average, but up to 57% in some populations) while having variable effects on other lipid parameters.

Primary Effects on Lipid Parameters

• Oral contraceptives containing ethinyl estradiol, including Triquilar, consistently increase plasma triglyceride levels by 20-30% on average, though increases of up to 57% have been documented in some populations 1, 2
• The estrogen component (ethinyl estradiol) is primarily responsible for the triglyceride-elevating effect, while the progestin component (levonorgestrel) tends to partially counteract this effect 1, 2
• Studies specifically examining triphasic levonorgestrel/ethinyl estradiol combinations show moderate elevations in plasma triglycerides, with the highest increases observed in triphasic formulations compared to monophasic ones 3, 4

Effects on Other Lipid Parameters

• Total cholesterol levels may increase moderately with Triquilar use 5, 4
• HDL cholesterol effects vary by formulation:
  • Triphasic levonorgestrel/ethinyl estradiol combinations like Triquilar may cause minor reductions in HDL cholesterol 3
  • HDL subfraction distribution may shift, with potential increases in HDL3 and decreases in HDL2 cholesterol 5, 6
• LDL cholesterol may increase with triphasic levonorgestrel formulations 5, 3
• LDL particle size tends to decrease with both monophasic and triphasic formulations, shifting from pattern A toward pattern I 5

Clinical Significance and Monitoring

• Despite these changes, screening for hyperlipidemia before initiation of hormonal contraceptives is not necessary according to current guidelines due to the low prevalence of undiagnosed hyperlipidemia in women of reproductive age 1, 2
• The clinical significance of these lipid changes remains unclear, with studies showing mixed results about their effects on cardiovascular risk 1, 2
• Women with abnormal lipid levels at baseline generally do not have increased risk for adverse changes to their lipid profiles when using hormonal methods 1
• For women with pre-existing hypertriglyceridemia, oral contraceptives should be used with caution (U.S. MEC 2/3, depending on the severity of hyperlipidemia and presence of other cardiovascular risk factors) 1, 2

Special Considerations

• Oral estrogens are listed among medications that can cause very high triglycerides potentially associated with pancreatitis 1
• For women who develop significant hypertriglyceridemia while taking Triquilar, consider:
  • Lower estrogen-containing preparations
  • Alternative contraceptive methods that don't contain estrogen 2
• The estrogenicity of combined oral contraceptives (measured by the ethinyl estradiol/levonorgestrel ratio) correlates with their effects on lipid profiles - higher ratios generally cause greater increases in triglycerides but less reduction in HDL cholesterol 3

Long-Term Effects

• Changes in lipid parameters tend to stabilize over time, with some studies showing that many initially altered lipid values return toward baseline after extended use (24 months) 6
• The overall clinical effect of these lipid changes on cardiovascular risk is considered minimal in most healthy women 1, 2