HMG: Side Effects

Safety Notice#

The safety profile of HMG in humans has not been established through controlled clinical trials. The information below is derived primarily from animal studies and should be interpreted accordingly.

Documented Adverse Effects#

Objective. To summarize documented adverse effects of human menopausal gonadotropin (hMG; menotropins) from animal studies and human reports, with frequency and severity where available.

Clarification of term. HMG here refers to human menopausal gonadotropin/menotropins (including highly purified hMG such as Menopur).

Animal data. Direct animal toxicology reports specifically attributing systemic organ toxicity, genotoxicity, or mortality to hMG were not identified in the accessible sources scanned. A rat histologic study using hMG in an ovarian model with nandrolone did not attribute systemic toxicity to hMG; quantitative animal adverse-effect rates for hMG were not reported in retrieved texts. This represents a gap in available evidence from this search sweep and should be interpreted as “no explicit signals found,” not proof of absence of risk.

Human clinical data with frequencies and severity.

• Ovarian hyperstimulation syndrome (OHSS). In an assessor-blinded RCT of IVF comparing HP-hMG to rFSH (n=731 randomized), OHSS occurred in 13/363 (3.6%) with HP-hMG vs 10/368 (2.7%) with rFSH; moderate/severe early OHSS in 5/363 (1.4%) and moderate/severe late OHSS in 3/363 (0.8%) in the HP-hMG arm. Late moderate/severe OHSS cases were associated with clinical pregnancy, and some occurred in twin pregnancies (two in HP-hMG). In high responders in the MEGASET-HR RCT, OHSS with HP-hMG was 30/310 (9.7%), with severity: mild 7/310 (2.3%), moderate 15/310 (4.8%), severe 8/310 (2.6%); incidence was higher with rFSH (21.4%) in the same study.

• Injection-site reactions. In an RCT comparing subcutaneous HP-hMG (Menopur) vs a less purified menotropins product (Repronex), injection-site reactions occurred in 3/61 (4.9%) vs 22/64 (34.4%), respectively (P<0.001). Menopur reactions were transient and mild–moderate; one severe OHSS occurred in the Menopur arm (1/61) and two OHSS (mild/moderate) in Repronex (2/64) (keye2005subcutaneouslyadministeredmenopur(r) pages 3-5, keye2005subcutaneouslyadministeredmenopur(r) pages 1-2).

• Common treatment-emergent adverse events (TEAEs). In MEGASET-HR, overall TEAEs occurred in 179/310 (57.7%) with HP-hMG. Frequent events included procedural pain 71/310 (22.9%); nausea 77/619 (12.4% overall study); abdominal distension 60/619 (9.7% overall); headache 51/619 (8.2% overall); abdominal pain 45/619 (7.3% overall); and vaginal hemorrhage 43/619 (6.9% overall). Serious TEAEs occurred in 8/310 (2.6%) in the HP-hMG arm; no deaths. In Andersen 2006, overall AE incidence was ~51% in HP-hMG vs 49% in rFSH, with common events including pelvic pain (6%), headache (5%), post-procedural pain (3–4%), nausea (2–4%), and abdominal distension (2–3%).

• Multiple gestation. In the Andersen RCT, twin pregnancies occurred in both groups; late moderate/severe OHSS cases were linked to clinical pregnancy and included twin pregnancies (two in HP-hMG), but an overall multiple gestation incidence specific to hMG was not uniquely quantified in the excerpts.

• Thromboembolism. The RCTs summarized did not report explicit venous thromboembolism (VTE) incidence attributable to hMG within the excerpts reviewed. Clinically, VTE risk is recognized to increase with severe OHSS, but quantitative VTE rates specific to hMG arms were not provided in these reports.

• Hypersensitivity/anaphylaxis. The highlighted RCTs did not report anaphylaxis events; explicit incidence could not be derived from these trial excerpts (keye2005subcutaneouslyadministeredmenopur(r) pages 3-5,, ).

Evidence summary table.

Conclusions. In human studies, the principal risk with hMG is OHSS, with incidence ranging from ~3–4% in general IVF populations to ~10% in high responders, and with reported severe OHSS around 2–3% in high-responder cohorts; late moderate/severe OHSS is associated with pregnancy and sometimes with twin gestations. Injection-site reactions are substantially less frequent with highly purified hMG (Menopur) than with older, less purified menotropins. Common non-serious AEs include procedural pain, nausea, abdominal discomfort/distension, and headache. Serious TEAEs are uncommon (~2–3%), and deaths were not reported in the cited RCTs. Explicit VTE and anaphylaxis rates were not reported in these RCT excerpts; VTE is a recognized complication primarily in the context of severe OHSS. Animal toxicity data directly attributable to hMG were not identified in the retrieved sources and remain a gap in this summary pages 3-5,, NCT00884221).

Contraindications#

Objective We summarize known contraindications and drug–drug interactions for HMG‑CoA reductase inhibitors (statins), distinguishing class‑wide versus agent‑specific considerations and adding mechanism‑based (theoretical) interactions.

Class‑wide contraindications

• Pregnancy and lactation: Historically contraindicated because of potential fetal risk and limited safety data; if lipid therapy is essential during pregnancy (e.g., severe familial hypercholesterolemia), management should be individualized with specialists.
• Active liver disease or unexplained persistent transaminase elevations: Avoid initiation; discontinue if significant hepatic injury is suspected.

Mechanistic basis for interactions (applies variably by agent)

• CYP metabolism: Simvastatin and lovastatin are most CYP3A4‑dependent; atorvastatin is partially CYP3A4; fluvastatin/rosuvastatin/pitavastatin rely more on CYP2C9 or UGTs; pravastatin has minimal CYP metabolism.
• Transporters: Hepatic uptake by OATP1B1/1B3 and efflux by BCRP and P‑gp are key; inhibition increases systemic exposure and myopathy risk.

Clinically important interacting drugs and foods

• Strong CYP3A4 inhibitors: Macrolides (clarithromycin, erythromycin), azole antifungals (itraconazole, ketoconazole, posaconazole), HIV/HCV protease inhibitors and boosters (ritonavir, cobicistat) markedly raise simvastatin/lovastatin and, to a lesser extent, atorvastatin; avoid simvastatin/lovastatin with these; prefer non‑CYP3A4 statins or reduce dose with close monitoring.
• Grapefruit juice: Mechanism‑based intestinal CYP3A4 inhibition increases exposure of simvastatin, lovastatin, and atorvastatin; avoid concomitant intake.
• Transporter inhibitors (OATP1B1/BCRP): Cyclosporine and gemfibrozil substantially increase statin exposure; cyclosporine can raise rosuvastatin AUC several‑fold; avoid gemfibrozil with any statin and prefer fenofibrate if a fibrate is needed; use very low statin doses or alternative statins with cyclosporine.
• Moderate CYP/transport effects: Verapamil/diltiazem, amlodipine, amiodarone, ranolazine increase exposure of simvastatin (and sometimes lovastatin/atorvastatin); follow label dose caps for simvastatin when coadministered, or select a statin with lower interaction risk.
• CYP3A4 inducers: Rifampin, carbamazepine, phenytoin, St. John’s wort can reduce exposure and efficacy of simvastatin/lovastatin/atorvastatin; consider switching to rosuvastatin or pitavastatin.
• Antiretrovirals: Protease inhibitors have major interactions with simvastatin/lovastatin (contraindicated); fluvastatin or pitavastatin are preferred; NRTIs and most integrase inhibitors have minimal interaction potential.
• Warfarin (VKAs): INR changes reported with some statins (e.g., fluvastatin, rosuvastatin, lovastatin); monitor INR on statin initiation or dose change.
• Additive myotoxicity: Concomitant colchicine or high‑dose niacin increases myopathy/rhabdomyolysis risk; use caution and monitor.

Agent‑specific highlights

• Simvastatin/lovastatin (CYP3A4 substrates): Contraindicated with strong CYP3A4 inhibitors and many ritonavir‑boosted regimens; avoid grapefruit juice; adhere to dose caps with verapamil, diltiazem, amlodipine, amiodarone, and ranolazine to mitigate myopathy risk.
• Atorvastatin: Partially CYP3A4; exposure increases with strong inhibitors but typically less than simvastatin/lovastatin; still avoid potent inhibitors or use the lowest effective dose with monitoring; grapefruit juice can increase exposure.
• Rosuvastatin: Limited CYP metabolism; exposure can increase markedly with OATP1B1/BCRP inhibition (e.g., cyclosporine), warranting low starting doses or alternative statin.
• Pravastatin: Minimal CYP metabolism; fewer CYP interactions; still susceptible to transporter‑mediated DDIs (e.g., cyclosporine).
• Fluvastatin: CYP2C9 substrate; fewer CYP3A4 interactions; monitor with warfarin due to CYP2C9 pathway.
• Pitavastatin: Primarily UGT metabolism; low CYP3A4 involvement; among safer options with protease inhibitors; still subject to OATP‑mediated interactions.

Theoretical interactions based on mechanism

• Any strong CYP3A4 inhibitor is expected to increase exposure and myopathy risk with simvastatin/lovastatin and to a lesser degree atorvastatin; any strong inducer may reduce their efficacy.
• Inhibitors of OATP1B1/1B3 and/or BCRP (e.g., cyclosporine; some DAAs or antibiotics) may raise rosuvastatin, pravastatin, and other statin levels; P‑gp inhibitors may increase exposure for P‑gp substrate statins.
• Pharmacogenetics: SLCO1B1 reduced‑function variants increase statin levels and myopathy risk, especially for simvastatin; DDIs that inhibit OATP compound this risk.

Management principles

• Prefer statins with lower interaction liability (e.g., pravastatin, rosuvastatin, pitavastatin) in patients requiring CYP3A4 inhibitors/boosted ART.
• Avoid gemfibrozil with any statin; if a fibrate is required, use fenofibrate cautiously with monitoring.
• Avoid grapefruit juice with CYP3A4‑metabolized statins.
• With cyclosporine, use very low statin doses or alternative agents; tacrolimus has substantially lower transporter inhibition and less interaction potential but still warrants monitoring.
• Monitor INR when initiating or changing statins in patients on warfarin.

Embedded reference table

Toxicology#

Objective: Define what HMG refers to and summarize its toxicology.

Interpretation and scope HMG here is interpreted as sodium (N‑)hydroxymethylglycinate (also called sodium hydroxymethylglycinate; SMG), a cosmetic preservative that can release formaldehyde under certain conditions. This interpretation is supported by preservative-focused literature explicitly listing SMG and providing acute toxicity and genotoxicity summaries.

Acute toxicity (LD50)

• Oral, rat: LD50 ≈ 2,100 mg/kg bw. Reported in a peer‑reviewed preservative survey table.
• Dermal, rabbit: LD50 > 2,000 mg/kg bw.
• Inhalation: No LD50 located for SMG in retrieved sources.

Organ/system toxicity and repeated‑dose data

• SMG-specific repeated‑dose in vivo organ toxicity data (target organs, histopathology, clinical chemistry) were not found in the retrieved sources.
• In vitro cytotoxicity: Human skin fibroblasts exposed to SMG showed cell death at 5 mM and 1 mM with viability at 0.1 mM, 0.01 mM, and 0.001 mM after 24 h exposure plus 48 h recovery.
• Context from formaldehyde (the species SMG can release): A 2‑year rat drinking‑water study for formaldehyde reports an oral NOAEL of 15 mg/kg/day; effects at higher doses include gastric mucosal lesions and kidney histopathology. An oral RfD of 0.2 mg/kg/day has been derived from such data.

Mutagenicity/genotoxicity

• Ames bacterial reverse‑mutation test: negative when tested as 100% sodium hydroxymethylglycinate.
• In vivo mouse micronucleus: negative.
• Rat hepatocyte DNA repair and UDS assays: negative.
• Overall, the retrieved assays do not indicate mutagenicity or genotoxicity for SMG.

Dose–response relationships

• Specific NOAEL/LOAEL or benchmark doses for SMG were not identified in retrieved sources.
• As contextual information, formaldehyde repeated‑dose data indicate a NOAEL of 15 mg/kg/day in rats (drinking‑water), with gastrointestinal and renal histopathology at higher doses.

pH and formaldehyde‑release considerations

• The preservative literature classifies SMG as a formaldehyde‑releasing agent. While the retrieved excerpts did not quantify pH‑dependent release for SMG specifically, the broader formaldehyde‑releaser context notes that free formaldehyde content and release influence local irritation/sensitization risk; elicitation is uncommon below ~0.025–0.05% free formaldehyde in sensitized individuals. Additional SMG‑specific release kinetics were not present in the retrieved texts.

Human sensitization/contact allergy

• Formaldehyde and formaldehyde‑releasers are recognized skin sensitizers; elicitation thresholds in sensitized humans are reported for free formaldehyde as above. The retrieved excerpts did not provide SMG‑specific human patch‑test or incidence data; thus only contextual evidence from formaldehyde/releasers can be cited here.

Conclusions

• Acute toxicity: SMG has moderate acute oral toxicity in rats (LD50 ~2,100 mg/kg) and low acute dermal toxicity in rabbits (>2,000 mg/kg); inhalation LD50 not located.
• Organ toxicity: No SMG-specific repeated‑dose in vivo organ toxicity studies were identified; in vitro shows cytotoxicity at ≥1 mM to human skin fibroblasts. Formaldehyde, a potential decomposition/release product, shows gastrointestinal and renal target‑organ toxicity in long‑term rodent studies with an oral NOAEL of 15 mg/kg/day.
• Mutagenicity: Available assays for SMG (Ames, mouse micronucleus, rat hepatocyte UDS/DNA repair) are negative.
• Dose–response: No direct SMG NOAEL/LOAEL or BMD found; formaldehyde NOAEL provides contextual hazard information.
• Sensitization: While SMG-specific human data were not retrieved, formaldehyde/releasers are established skin sensitizers; elicitation in sensitized individuals is uncommon at free formaldehyde below ~0.025–0.05%.

Key gaps

• SMG-specific repeated‑dose in vivo organ toxicity and quantitative dose–response (NOAEL/LOAEL) were not identified in the retrieved evidence. Further targeted searches (e.g., CIR or SCCS ingredient opinions, manufacturer dossiers) may provide additional data.

Evidence Gaps#

• Human adverse event data is limited to anecdotal reports
• Systematic adverse event monitoring has not been conducted
• Drug interaction studies are incomplete
• Long-term safety profiles are unknown

Related Reading#

• HMG overview and research guide
• HMG dosing protocols
• HMG risks and legal status