Drug absorption is affected by slower gastric emptying and slower bowel and colonic transit time. The increased plasma volume, change in protein binding, and lower ratio of lean muscle to adipose tissue during pregnancy may result in a greater volume of drug distribution for lipophilic drugs.
Do you metabolize drugs faster when pregnant?
Results from clinical pharmacokinetic studies indicate clearances of drugs metabolized by selected drug metabolizing enzymes (e.g., CYP2D6 and CYP3A4) increased, whereas those of drugs metabolized by other enzymes (e.g., CYP1A2) decreased during pregnancy as compared to non-pregnant women [7, 9, 22].
How does pregnancy affect drug elimination?
As the glomerular filtration rate usually increases during pregnancy, renal drug elimination is generally enhanced, whereas hepatic drug metabolism may increase, decrease or remain unchanged.
How does pregnancy affect pharmacodynamics?
Physiologic changes in pregnancy induce profound alterations to the pharmacokinetic properties of many medications. These changes affect distribution, absorption, metabolism, and excretion of drugs, and thus may impact their pharmacodynamic properties during pregnancy.
How does pregnancy affect volume of distribution?
Pregnancy is associated with increase in tidal volume by 30–50%, which starts early in the first trimester. While the respiratory rate is not different compared to non-pregnant state, minute ventilation (the product of respiratory rate and tidal volume) is significantly increased, similarly, by 30–50%.
Are medications less effective when pregnant?
As a rule of thumb, the drug’s elimination route is the most crucial factor to consider. If the drug is mainly excreted unchanged through the kidneys, serum concentrations will often decline by almost 50 % during the pregnancy (Fig.
Does your metabolism slow down when you are pregnant?
This increased metabolic rate may put pregnant women at a higher risk of hypoglycemia, or low blood sugar. Although the metabolic rate may drop slightly as the pregnancy reaches term, it remains elevated over prepregnancy levels for several weeks postpartum.
Does glomerular filtration increase during pregnancy?
Glomerular filtration rate increases 40% to 50% in normal pregnancy. Creatinine clearance by 24-hour urine collection is the current standard for measurement of glomerular filtration rate in pregnant women.
Which factors in a patient would influence GI absorption of medications?
Physiological factors within the gut that affect oral drug absorption include gastric emptying rate and intestinal motility, the pH of the gastrointestinal fluids, the activity of gastrointestinal drug metabolising enzymes (e.g. monoamine oxidase and dopa decarboxylase) or drug metabolising bacteria and the surface …
Which form of drug requires slow absorption in the body in a high alkaline pH environment?
Enteric coating of aspirin necessitates alkaline conditions for absorption, which is thus delayed until the small intestine (Awtry and Loscalzo, 2000).
What is the significance of pregnancy induced Hypervolemia?
The pregnancy-induced hypervolemia is thought to provide survival advantage to the pregnant women, protecting her from the hemodynamic instability caused by the blood loss at the time of delivery. Up to 75% of the increase in total blood volume is through the plasma volume.
Can an AED be used on a pregnant woman?
CPR in a pregnant woman should be done in cycles of 30 compressions and two breaths. It is also safe to use an automated external defibrillator, or AED, if one is available. Bystanders should not be afraid they might hurt the unborn baby, Jeejeebhoy said.
What mechanism is involved during drug transport across the placental barrier?
Nutrient and drug transfer across the placenta are by passive diffusion, facilitated diffusion, active transport, and pinocytosis. Placental drug transfer is dependent on the physical properties of the placental membrane and on the pharmacological properties of the drug.
Which site of drug absorption is considered to have the largest surface area?
Which of the following sites of drug absorption is considered to have an exceptionally large surface area for drug absorption? The lungs have a large surface area for absorption of anesthetic gases and a few other drugs.
What is the rule of thumb regarding medications during pregnancy?
A good rule of thumb: Use as few medications (over- the-counter or prescription) as possible in pregnancy. Your baby is most vulnerable during the first trimester. Many medications are safe when used properly during pregnancy, but we must look at each situation.