Comparison
Alpha-Lipoic Acid vs PT-141
Side-by-side of Alpha-Lipoic Acid and PT-141. Every row below is pulled from the compound schema and will update as our data grows. For deeper reads, follow through to each compound page.
Alpha-Lipoic Acid
Alpha lipoic acid supplement guide: 600 mg/day oral dosing, R-ALA vs racemic absorption, neuropathy trial data, antioxidant mechanism, interactions.
PT-141
PT-141 peptide (bremelanotide, Vyleesi): MC4R agonist for libido and erectile dysfunction. 1.75 mg subcutaneous, 30 to 60 min onset, 2 to 4 h half-life.
Effects at a glance
Alpha-Lipoic Acid
- •Approved Rx for diabetic neuropathy in Germany at 600 mg/day IV (Thioctacid) since 1960s
- •Improves neuropathy symptoms (TSS, NIS) at 600 mg/day IV across ALADIN and SYDNEY trials
- •R-ALA enantiomer absorbs 40-100% better than racemic mixtures
- •Activates AMPK; produces small HbA1c reductions in T2DM
- •Plasma half-life ~30 minutes; split dosing or sustained-release is standard
- •Hypoglycemia risk with insulin or sulfonylureas; medication adjustment may be required
PT-141
- •Cyclic 7-amino-acid synthetic peptide and melanocortin receptor agonist (MC4R-preferring)
- •FDA approved in 2019 as Vyleesi for hypoactive sexual desire disorder in pre-menopausal women
- •Acts centrally on hypothalamic sexual-desire circuits rather than peripherally on vasculature
- •On-demand dosing: subcutaneous 1.75 mg approximately 45 minutes before sexual activity
- •Common adverse effects: nausea (~40%), flushing, headache, injection-site reactions, hyperpigmentation
- •Off-label male ED use is documented but not FDA approved; mechanism is distinct from PDE5 inhibitors
Side-by-side
| Attribute | Alpha-Lipoic Acid | PT-141 |
|---|---|---|
| Category | supplement | peptide |
| Also known as | ALA, thioctic acid, R-ALA, R-lipoic acid | Bremelanotide, Vyleesi |
| Half-life (hr) ↗ | 0.5 | 2.7 |
| Typical dose (mg) ↗ | 600 | 1.75 |
| Dosing frequency | 1 to 3 times daily on empty stomach | as needed (max once per 24 hours, max 8 per month) |
| Routes | oral, iv | subcutaneous |
| Onset (hr) | 0.5 | 0.75 |
| Peak (hr) | 1 | 1.5 |
| Molecular weight | 206.33 | 1025.18 |
| Molecular formula | C8H14O2S2 | C50H68N14O10 |
| Mechanism | Dual lipid- and water-soluble antioxidant; redox cycles with dihydrolipoic acid (DHLA) to scavenge ROS, regenerate vitamin E and C, and chelate transition metals. Activates AMPK in liver and muscle; cofactor for pyruvate and alpha-ketoglutarate dehydrogenase complexes. | Synthetic agonist of melanocortin receptors with preference for MC4R, expressed in hypothalamic and limbic circuits regulating sexual motivation. Engages central pathways distinct from peripheral PDE5-mediated vasodilation. |
| Legal status | Dietary supplement (US, UK, Canada, most EU); prescription drug for diabetic neuropathy in Germany | Prescription only as Vyleesi; FDA-approved 2019 for HSDD in pre-menopausal women. Compounded versions sold off-label for male sexual function are research-use-only grey market. |
| WADA status | allowed | allowed |
| DEA / Rx | Not scheduled | Rx only (not a controlled substance) for the FDA-approved Vyleesi formulation |
| Pregnancy | Insufficient data; precautionary avoidance | Not recommended; contraindicated during pregnancy per Vyleesi label |
| CAS | 62-46-4 | 189691-06-3 |
| PubChem CID | 864 | 9941379 |
| Wikidata | Q161227 | Q422059 |
Safety profile
Alpha-Lipoic Acid
Common side effects
- nausea
- abdominal discomfort
- diarrhea
- sulfurous odor
- rash (rare)
Contraindications
- pregnancy and lactation (insufficient safety data)
- active insulin autoimmune syndrome predisposition
Interactions
- insulin and sulfonylureas: additive hypoglycemia; medication dose adjustment may be required(major)
- thyroid hormone: may reduce T4 to T3 conversion at high doses(moderate)
- biotin: ALA competes with biotin uptake; chronic use can induce biotin insufficiency(minor)
- iron supplements: ALA chelates iron and reduces absorption; separate dosing(moderate)
- chemotherapy (oxidative-stress-dependent agents): theoretical interference; coordinate with oncology team(moderate)
PT-141
Common side effects
- nausea (~40%)
- flushing
- headache
- injection-site reactions
- hyperpigmentation (focal, gums, face, breasts)
- transient blood pressure increase (~6 mmHg systolic)
Contraindications
- uncontrolled hypertension
- established cardiovascular disease
- pregnancy
- naltrexone co-administration (reduces opioid efficacy due to MC receptor crosstalk)
Interactions
- naltrexone (oral): bremelanotide reduces oral naltrexone exposure significantly; avoid co-administration(major)
- antihypertensives: transient BP rise after bremelanotide can offset BP control(moderate)
- PDE5 inhibitors (sildenafil, tadalafil): no documented adverse interaction; mechanisms are non-overlapping(minor)
Which Should You Take?
Alpha-Lipoic Acid comes out ahead for most readers on the criteria we weight: 3 catalogued goals, OTC dietary supplement, oral dosing, with a Tier-B outcome catalogued. PT-141 is the right call when one of the conditionals below applies.
- → If your priority is metabolic health and glucose control, pick Alpha-Lipoic Acid.
- → If your priority is healthspan extension, pick Alpha-Lipoic Acid.
- → If your priority is sexual function, pick PT-141.
- → If your priority is libido, pick PT-141.
Edge case: If you want to avoid research-only / gray-market sourcing, Alpha-Lipoic Acid is the more accessible choice.
Default choice: Alpha-Lipoic Acid. Lower friction to source, and broader goal coverage. Reach for PT-141 only if your priority sits squarely in the goals it owns above.
This verdict is generated from each compound's schema (goals, legal status, evidence outcomes, dosing route). It updates automatically as our compound data evolves; the deeper read sits on each individual compound page.
Common questions
What is the difference between Alpha-Lipoic Acid and PT-141?
Alpha-Lipoic Acid and PT-141 differ in category (supplement vs peptide), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Alpha-Lipoic Acid or PT-141?
Alpha-Lipoic Acid half-life is 0.5 hours; PT-141 half-life is 2.7 hours.
Can you stack Alpha-Lipoic Acid with PT-141?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
Go deeper