Pregabalin
Pregabalin (Lyrica)
Clinical Summary
Pregabalin is a gabapentinoid used primarily for neuropathic pain, fibromyalgia, and as an adjunct for seizures.
Documented on handwritten prescription as "Pregaserve" — likely brand name containing pregabalin 75 mg.
Newly documented from handwritten prescription dated 2026-05-04. Dose: 75 mg once daily (morning, 1-0-0).
[!info] Post-2022 Medication: Neuropathy Developed After 2022
Pregabalin is absent from the November 2022 medication list (raw/clinic-notes/2026-05-06_note.md). It was added to the regimen at an unknown date between November 2022 and May 2026. This confirms that the neuropathic pain indication (presumed diabetic neuropathy) developed or was recognized after 2022.
Dosing History
| Date | Dose | Frequency | Route | Context |
|---|---|---|---|---|
| 2022-11-25 | — | — | — | NOT on Nov 2022 Rx — neuropathy not yet diagnosed/treated |
| Between 2022–2026 | — | — | — | Pregabalin added at unknown date |
| 2026-05-04 | 75 mg | Once daily (morning, 1-0-0) | Oral | Documented from handwritten Rx ("Pregaserve") |
This medication was NOT previously documented in any ingested raw source. No documentation of neuropathic pain symptoms, diabetic neuropathy assessment, or other indication for pregabalin. Indication is PRESUMED.
Indication (PRESUMED)
Most likely: Diabetic peripheral neuropathy (DPN)
Pregabalin is FDA-approved for:
1. Diabetic peripheral neuropathy (DPN) — most likely indication for Ishamma given Diabetes Mellitus diagnosis
2. Postherpetic neuralgia (Ishamma has history of Herpes Zoster, but no documented PHN)
3. Fibromyalgia
4. Adjunct for partial-onset seizures
5. Generalized anxiety disorder (not FDA-approved in US, but approved in Europe)
No symptoms documented:
- No clinic notes documenting neuropathic pain symptoms (burning, tingling, allodynia)
- No neurological examination findings documented
- No neuropathy screening tools (monofilament, vibration, ankle reflexes) documented
This is a significant clinical documentation gap.
Pharmacology
- Drug class: Gabapentinoid (alpha-2-delta ligand)
- Mechanism: Binds to alpha-2-delta subunit of voltage-gated calcium channels, reducing calcium influx and neurotransmitter release (glutamate, substance P, norepinephrine). Result: reduced neuronal excitability and neuropathic pain.
- Half-life: ~6.3 hours
- Excretion: Renal (unchanged) — requires dose adjustment in renal impairment
- Standard dosing for DPN: 150–600 mg/day in 2–3 divided doses (current: 75 mg once daily — subtherapeutic as monotherapy)
Dosing Analysis
| Indication | Standard Dose | Ishamma's Dose | Assessment |
|---|---|---|---|
| Diabetic neuropathy | 150–600 mg/day (divided b.i.d. or t.i.d.) | 75 mg once daily | Subtherapeutic — below minimum effective dose |
| Postherpetic neuralgia | 150–600 mg/day | 75 mg once daily | Subtherapeutic |
| Generalized anxiety | 150–600 mg/day | 75 mg once daily | Subtherapeutic |
75 mg once daily is below the minimum effective dose for all FDA-approved indications. This may represent:
1. Initial titration dose (standard start: 75 mg b.i.d., then increase)
2. Elderly/renal dosing (reduced dose for safety in age 81 + concern for sedation/falls)
3. Off-label low-dose use for mild symptomsIf this is intended as therapeutic dosing (not just titration), it is likely inadequate.
Monitoring — CRITICAL in Elderly
| Parameter | Frequency | Rationale | Ishamma Status |
|---|---|---|---|
| Renal function | Baseline, then periodic | Pregabalin renally excreted; dose adjustment required if CrCl <60 mL/min | Creatinine stable 0.7–0.9 mg/dL (normal) |
| Fall risk / balance | Each visit | High fall risk in elderly — pregabalin causes dizziness, ataxia, somnolence | Not documented |
| Mental status / cognition | Each visit | CNS depression, confusion (especially in elderly) | Not documented |
| Weight | Periodic | Weight gain is common side effect | Not documented |
| Neuropathic pain score | Each visit (if DPN is indication) | Assess treatment efficacy | No baseline pain assessment documented |
[!danger] Fall Risk in Elderly
Pregabalin is associated with dizziness (30%), somnolence (22%), and ataxia (6%) in clinical trials — higher risk in elderly. Ishamma is age 81. This is a significant fall risk.American Geriatrics Society Beers Criteria: Pregabalin is listed as "use with caution" in older adults due to CNS effects and fall risk.
Drug Interactions
- CNS depressants (benzodiazepines, opioids, alcohol): Additive sedation and respiratory depression risk
- ACE inhibitors / ARBs: Increased angioedema risk (rare)
- Thiazolidinediones (pioglitazone, rosiglitazone): Increased peripheral edema and weight gain risk (not applicable — Ishamma not on TZDs)
- No CYP450 interactions (not metabolized, renally excreted unchanged)
Adverse Effects
| Effect | Frequency | Impact in Ishamma (Age 81) |
|---|---|---|
| Dizziness | 30% | High fall risk |
| Somnolence | 22% | CNS depression, fall risk |
| Peripheral edema | 6–16% | Compounded by nifedipine (CCB also causes edema) |
| Weight gain | 5–16% | Monitor |
| Ataxia | 6% | Fall risk |
| Confusion / cognitive impairment | Rare but increased in elderly | Monitor cognition |
| Angioedema | Rare | Increased risk with ARB (losartan) |
Pregabalin causes peripheral edema in 6–16% of patients. Ishamma is also on Nifedipine (calcium channel blocker), which causes edema in 10–30%. Combined use increases edema risk.
Renal Dosing
Pregabalin requires dose adjustment in renal impairment:
| CrCl (mL/min) | Dose Adjustment |
|---|---|
| ≥60 | No adjustment |
| 30–60 | Reduce dose by 25–50% |
| 15–30 | Reduce dose by 50–75% |
| <15 (or dialysis) | Reduce dose by 75%; supplement after dialysis |
Ishamma's status: Creatinine 0.7–0.9 mg/dL (normal). Estimated CrCl >60 (likely). No dose adjustment required currently, but monitor renal function during AML treatment.
Related
- Diabetes Mellitus — Presumed indication (diabetic neuropathy)
- Herpes Zoster — History; postherpetic neuralgia is another possible indication (not documented)
- Renerve — Also prescribed for neuroprotection (B-vitamin complex)
- Nifedipine — Both cause peripheral edema; monitor for additive effect
- Losartan — Rare angioedema interaction with pregabalin
- Creatinine — Monitor renal function (pregabalin renally excreted)
Medication page created during ingest of 2026-05-04 handwritten prescription. Indication presumed to be diabetic neuropathy, but NO clinical documentation of neuropathic symptoms exists in ingested sources.