Lec 21: Restarting Meds After Overdose

Question 1

What are the “7 Principles” to guide restarting meds after an OD?

Answer 1

1) Do they even need the med? look for opportunities for deprescribing.

2) Risk vs Benefit
3) PK vs Toxicokinetics
4) Is the pt experiencing withdrawal/discontinuation syndrome?
5) Is there a blood level that can be done?
–> USUALLY, if pt’s levels are in therapeutic range, they can be restarted on meds.

6) Is a drug interaction likely?
–> must ask, what we given anythign to pt to treat their poisioning that now might interact if we restart med?
–> and are we SWITCHIGN antidepressants, whcih may need a washout period?

7) Implementation and Minimizing risk

Question 2

If someone OD’s once, are they more likely to OD again vs someone who’s never?

Answer 2

yes! Majority of OD victims had another OD 9 months later.

Question 3

Principle 2: Risk vs. Benefit

• What is the FIRST question should you ask when asseessing this?
• what are 3 other questions to ask?

Answer 3

What’s the worst possible thing that could hapen if I restart the med right now?

1) does pt look toxic?
2) Pt disposition? and where are they going? home? psych unit? icu? a monitored bed?

2) are they a risk to themslelves or others if they continue to hold antipsychotics for ex?

Question 4

Principle 2:
- What are 4 characteristics of HIGH RISK situations, where you might considering delaying re-start.

Answer 4

• If still actively CNS depressed.
• Displaying elements of cardiotoxicity.
• If they’ve OD’d on a HYPOGLYCEMIC agent (sulfonylurea), have to be able to show they can control blood sugar withotu exogenous glu drip or octreotide antidote. Must show overnight fast = can control sugards on own.
• If showing any signs of opiate toxidrome.

Question 5

Principle 3: Kinetics

• 97% of drugs are eliminated in how many half lives?
• 99.9%?

Answer 5

• 5 half lives.
• 99.9% in 10 half lives. [from steady state]

Question 6

Principle 3: Kinetics

• How many days does it take for MOST pts to recover from an overdose?

Answer 6

1-4 days.

Question 7

Principle 3: Kinetics

• What are some important considerations when assessing kinetics of ODs?

Answer 7

• ACTIVE METABOLITES: Are we considering active metabolites from drugs.
• GENETIC VARIATION IN CYP ENZYMES:
• SATURATION OF ENZYMES: what other factors can saturate enzymes?
• CHANGES IN PHYSL MILIEU: Changing blood/urine pH can affect elim of certain drugs

Question 8

Principle 4: is the pt in withdrawal?

What acronym can you used to assess withdrawal sx? what does it stand for?

Answer 8

Flu like symptoms
Insomnia
Nausea
Imbalance
Sensory Disturbances
Hyperarousal (Agitation/Anxiety)

Question 9

What are the most likely culprits leading to withdrawal?

Answer 9

• SSRIs
• SNRIs
• Baclofen
• Opiates
• Benzodiazepines
• Ethanol
• Beta-blockers
• Clonidine

Question 10

Which drug is known for mimicking brain death on overdose?

Answer 10

Baclofen

Question 11

What is an unlikely drug associated with withdrawal?

• what does it look like clinically?
• what is the trx? (2)

Answer 11

baclofen! GABA-B agent.

It looks like ALCOHOL WITHDRAWAL. {think: ACHAT - ass hat}
Agitation
Confusion
Hallucinations
Autonomic volatility
Tremors

• Restart at LOWER dose then titrate up slowly.
• Can use BENZOS.

Question 12

Principle 7:
- Which drug should you restart first?

Answer 12

• most clinically imp. drug first; if multiple are imp, restart one with SHORTEST HALF LIFE first.