Therapeutic considerations in pregnant or lactating animals

Question 1

Considerations for therapeutics in pregnancy

Answer 1

What is the effect on pregnancy
What is the effect on the fetus:
Teratogenesis
At birth

Is there a label indication
Balance between treating the dam and potential harm to fetus
Are dose adjustments required for safety/efficacy reason

Question 2

Therapeutic considerations for lactating animal

Answer 2

What is the effect on the neonate
Is there any effect on lactation
Is the drug licensed
Metabolic status of the dam- may be under stress due to energy requirements of lactation
New route of elimination
Milk withdrawal times & human consumption

Question 3

ADME for durgs in pregancy

Answer 3

Absorption: Reduced abdominal space. Increased gastric pH
Distribution: Additional compartment/plasma volume. Drugs with high Vd more likely to cross the placenta
Metabolism: Altered metabolism due to additional need for detoxification
Excretion: Alkalosis/acidosis in dam can lead to alter excretion

Ion trapping of drugs in fetus (particularly basic drugs) I.e. bupivacine

Question 4

Trans-placental transfer of drug

Answer 4

If a drug can be absorbed orally it is likely to cross the placenta

Question 5

Pharmacokinetic considerations in lactation
which drugs most likely to go to milk

Answer 5

New route of drug elimination particularly drugs with:
Lipid soluble
Basic, non-ionised
Lower plasma protein binding

Some drugs are inactivated by milk
Mastitis may influence milk PH and/or influence blood flow to mammary gland
Most milk has high fat content and most drugs are lipophilic so may move into milk

Question 6

What type of drugs bind to plasma albumin

Answer 6

acidic

Question 7

what type of drugs bind to beta-globulin

Answer 7

Basic