In 2015, the National Health and Morbidity Survey reports that 47.7% of Malaysian adults aged 18 years and above have high blood cholesterol. This is a concern because high blood cholesterol increases your risk of heart diseases. Generally, there are two types of cholesterol; ‘bad’ cholesterol which are your low-density lipoprotein (LDL) and triglycerides (TG) that increases the risk of heart diseases, and ‘good’ cholesterol which is your high-density lipoprotein (HDL). Although high cholesterol is usually associated with genetics and unhealthy diet, one of the less common factors causing high cholesterol is use of certain medications. 

These are some of the medications that are used to treat various health conditions that may affect your blood cholesterol levels.

1. Thiazide diuretics – Thiazide diuretics are commonly prescribed for high blood pressure and high doses of thiazide diuretics (Hydrocholorothiazide) can increase LDL and TG levels. However, this effect may be temporary and your cholesterol levels may return to normal within one year of starting this medication. 
2. Beta blockers – Beta blockers are used in the treatment of heart failure and high blood pressure. Some beta blockers (eg. Propranolol, Metoprolol) have been found to increase TG levels and reduce HDL levels. However, not all beta-blockers confer the same risk. For instance, carvedilol is less likely to negatively affect blood cholesterol levels.
3. Progestin and estrogen -  Progestin, a hormone that can be found in some of the birth control pills in the market can increase LDL and decrease HDL levels. On the other hand, estrogen have beneficial effects on lowering LDL and increasing HDL, but has the tendency to increase TG. Therefore, when progestin is use together with estrogen in combined oral contraceptives, the overall effect on LDL and HDL levels is not significant, but there may be a slight increase in TG level.

It is important to note that if the effect of these medications on cholesterol levels is mild and usually does not outweigh the benefit that you may get from taking these medications. If you are worried about high cholesterol, speak to your health care provider about making lifestyle changes on your diet and exercise. Do not stop your prescribed medications before discussing with your doctor.

References:

1. Institute for Public Health (IPH) 2015. National Health and Morbidity Survey 2015 (NHMS 2015). Vol. II: Non-Communicable Diseases, Risk Factors & Other Health Problems;2015.