A case of probable oxybutynin-induced increase in liver enzymes

Figures & data

Figure 1 Liver enzymes levels during hospital stay.

Notes: On 7/4/2017, atorvastatin was suspended and mild decrease noted. When liver enzymes started to increase again, on 26/4/2017, escitalopram was suspended and they started to lower after few days. Oxybutynin was started on 6/5/2017, and the enzymes elevated again within a week. On 15/5/2017, oxybutynin was suspended and, in few days, a decrease in liver enzymes was noted.
Abbreviations: ALT, alanine aminotransferase; AST, aspartate aminotransferase.

Figure 2 ALT and AST levels during hospital stay.

Notes: After suspending atorvastatin, on 20/4/2017, a clear drop is noted. After suspending escitalopram due to repeated elevation, on 6/5/2017, the enzymes fell again, and oxybutynin was started on the same day. Within a week, elevation of liver enzymes occurred again, so oxybutynin was suspended on 15/5/2017 and the enzymes started to fall reaching baseline values in the following few days.
Abbreviations: ALT, alanine aminotransferase; AST, aspartate aminotransferase.

Table 1 Naranjo adverse drug reaction scale

ADR probability scale
Question	Yes	No	Do not know	Score
1. Are there previous conclusive reports on this reaction?	+1	0	0	0
2. Did the adverse event appear after the suspected drug was administered?	+2	−1	0	+2
3. Did the adverse event improve when the drug was discontinued or a specific antagonist was administered?	+1	0	0	+1
4. Did the adverse event reappear when the drug was re-administered?	+2	−1	0	0
5. Are there alternative causes that could on their own have caused the reaction?	−1	+2	0	+2
6. Did the reaction reappear when a placebo was given?	−1	+1	0	0
7. Was the drug detected in blood or other fluids in concentrations known to be toxic?	+1	0	0	0
8. Was the reaction more severe when the dose was increased or less severe when the dose was decreased?	+1	0	0	0
9. Did the patient have a similar reaction to the same or similar drugs in any previous exposure?	+1	0	0	0
10. Was the adverse event confirmed by any objective evidence?	+1	0	0	+1

Note: This suspected ADR is rated as “probable.”

Abbreviation: ADR, adverse drug reaction.