Pain-relieving suppositories during menstruation

1. The strongest evidence base for pain relief in primary dysmenorrhea is for nonsteroidal anti-inflammatory drugs (NSAIDs). Their effectiveness has been confirmed by systematic reviews and meta-analyses. [1]
2. Rectal suppositories with NSAIDs (eg, diclofenac or naproxen) and rectal forms of paracetamol are used when the oral route is difficult or a rapid effect is required; their effectiveness is comparable to oral forms in a number of studies. [2]
3. Vaginal suppositories containing cannabidiol or other non-traditional formulations show promising preliminary results, but large randomized studies are still limited; such options should be considered experimental or supportive.[3]
4. In chronic, resistant, or secondary dysmenorrhea, organic causes should be ruled out first and hormonal contraception considered as the primary therapy. NSAIDs in any form remain the initial treatment for symptoms. [4]

How and why suppositories can work for menstrual cramps - physiology and pharmacology

Menstrual pain is primarily associated with high levels of prostaglandins in the uterus, which induce smooth muscle spasms and sensitization of pain receptors. Blocking prostaglandin synthesis through cyclooxygenase inhibition provides an objective reduction in pain and discomfort. Nonsteroidal anti-inflammatory drugs target this mechanism. [5]

Rectal administration of the suppository bypasses gastrointestinal obstruction and vomiting, provides rapid absorption through the rectal venous network, and, in some cases, a higher local concentration of the active substance in the pelvic region. This is especially useful in cases of severe pain with nausea or poor tolerance of oral forms. [6]

Vaginal suppositories act locally on the pelvic organs; their effectiveness is presumed to be based on their proximity to the uterus and the possible local anti-inflammatory or neuromodulatory effects of their components. For a number of modern formulations, such as those with a high cannabidiol content, a mechanism of action via the endocannabinoid system and inflammation modulation has been proposed. Such mechanisms are currently supported by limited clinical data. [7]

Comparison of routes of administration: If an oral NSAID is well tolerated, it remains the standard. Suppositories are an alternative route when oral administration is contraindicated or when rapid and stable absorption is required. The decision on the route of administration should take into account contraindications, comorbidities, and patient preference. [8]

Rectal suppositories with nonsteroidal anti-inflammatory drugs - evidence and practice guideline

NSAIDs in various formulations consistently show superiority over placebo in reducing menstrual pain. The Cochrane review and large systematic reviews support the overall class effect of NSAIDs and indicate that there is insufficient evidence to support a clear superiority of any single agent based on differences in efficacy between individual drugs. [9]

Rectal forms of diclofenac and naproxen have been studied in a number of randomized trials and clinical trials. In controlled settings, rectal diclofenac suppositories provide comparable analgesia to oral regimens and are often preferred for nausea. When choosing a dose and frequency, it is important to follow the manufacturer's instructions and local regulatory guidelines. [10]

A practical regimen for an adult patient (approximate guideline; use only in accordance with the instructions and contraindications): diclofenac rectally 50 mg once, with the possibility of repeating after 6-8 hours if necessary; naproxen rectally 250-500 mg once, then 250 mg every 8-12 hours depending on the response. The duration of treatment is usually limited to 48-72 hours for cyclic pain episodes. The dosage table is below. [11]

Side effects and precautions are identical to the systemic effects of NSAIDs: risk of gastrointestinal bleeding and ulceration, effects on renal function during dehydration, interactions with anticoagulants and hypertensive drugs. If there are contraindications to NSAIDs, paracetamol or alternatives are preferred. [12]

Vaginal suppositories and new formulations - cannabidiol, herbal blends, topical gels

Vaginal formulations containing cannabidiol and certain plant extracts received the first real-world and quasi-exploratory evidence for improving menstrual symptoms in 2023-2024. The results indicate a reduction in the frequency and severity of pain and a reduced need for additional analgesics, but the design of most studies does not provide the level of evidence required for a randomized, double-blind study. Therefore, it is premature to consider such formulations as a standard. [13]

Some studies have evaluated vaginal suppositories containing camphor, resins, or plant extracts. Some have shown improvement in subjective symptoms, but methodological limitations and small sample sizes limit confidence. For clinical practice, such formulations can be considered as an adjunctive option in the absence of contraindications and with the patient's informed consent. [14]

If a patient chooses vaginal "natural" suppositories, it is important to check the ingredients for irritating additives, allergens, and preservatives, and to ensure the packaging is sterile. If local irritation develops or symptoms worsen, discontinue use and undergo an examination. [15]

Overall, vaginal suppositories with new active ingredients appear promising, but do not yet replace proven pharmacological strategies. Their use is appropriate within the context of clinical observation or when standard approaches are ineffective. [16]

Paracetamol in rectal form, combined and auxiliary suppositories

Rectal paracetamol (acetaminophen) remains a useful alternative when NSAIDs are contraindicated or when used in combination with other medications. Evidence shows that paracetamol is less effective than NSAIDs for primary dysmenorrhea, but it is safer when there is a risk of gastrointestinal complications. [17]

Combination rectal suppositories containing an antispasmodic and an analgesic are used in some countries and may provide additional symptomatic relief for severe uterine spasms. The safety profile of each component must be assessed. When using a pharmacological combination, select medications with proven tolerability and interaction safety. [18]

In obstetric and postoperative practice, rectal NSAIDs have long been used as a means of rapid pain relief; this provides additional confidence in the use of such forms for menstrual pain when appropriate indications are present. [19]

Safety, Contraindications, and Interactions - Practical Rules

The main contraindications to NSAIDs are active ulcerative lesions of the stomach and duodenum, severe liver or kidney failure, severe heart failure, and uncontrolled combination with anticoagulants. During pregnancy, most NSAIDs should be avoided, especially in the third trimester. Before prescribing the rectal form, check for a history of allergy to NSAIDs. [20]

When using rectal forms, it is important to warn of possible local sensitivity, and less commonly, rectification. With prolonged or frequent use of NSAIDs, monitor liver and kidney function and assess for signs of occult gastrointestinal bleeding. When taking anticoagulants concomitantly, coordinate treatment with a physician, as the risk of bleeding increases. [21]

Paracetamol is safer for peptic ulcers and those requiring anticoagulants, but overdose can cause severe liver failure. Dosage and total daily doses must be strictly adhered to. When combining medications, check the total dose of the active ingredient to avoid overdose. [22]

When using herbal vaginal suppositories, special attention should be paid to the risk of allergy and interaction with local microflora. If symptoms of local inflammation or discharge occur, discontinue use and undergo an examination. [23]

A practical algorithm for the doctor and the patient - steps in the clinic and at home

1. At the first visit, assess the nature of the pain, associated symptoms, chronic diseases, and medications; rule out secondary dysmenorrhea if any warning signs are present. If a secondary cause is suspected, refer the patient for examination. [24]
2. Offer an oral NSAID as initial therapy unless contraindicated; if the oral route is not possible, offer rectal suppositories of the appropriate NSAID or paracetamol. In cases of severe nausea, the rectal form is often preferred.[25]
3. If the patient is interested in vaginal "alternative" suppositories, discuss the level of evidence, potential risks, and offer them as an additional option with informed consent. Note the need to discontinue if a reaction occurs. [26]
4. If basic therapy is ineffective, consider hormonal contraception to control menstrual pain and refer the patient to a gynecologist for further diagnosis and management. [27]

Tables

Table 1 - Types of suppositories and their main uses

Suppository type	Active ingredient	Main indication	Comment
Rectal NSAIDs	Diclofenac, naproxen	Primary dysmenorrhea with intolerance to oral forms or nausea	Fast absorption, effective
Rectal paracetamol	Paracetamol	In case of contraindications to NSAIDs or combination	Less anti-inflammatory activity
Rectal combination	NSAID plus antispasmodic	Severe spasmodic pain	Requires safety assessment of the combination
Vaginal CBD and botanicals	CBD, plant extracts	Experimental option for pain reduction	Data is limited; discuss risks
Oil and herbal vaginal suppositories	Vegetable oils	Symptomatic support	Check the composition and sterility

Table 2 - Examples of doses and regimens

Preparation	Suppository form	Approximate dosage	Frequency
Diclofenac	Rectal 50 mg	50 mg once a day	Repeat after 6-8 hours if necessary; no more than 150 mg per day
Naproxen	Rectal 250-500 mg	250-500 mg once	250 mg every 8-12 hours; limit as directed
Paracetamol	Rectal 500-1000 mg	500-1000 mg once	Maximum 3,000-4,000 mg per day depending on the region
Combined	Depends on the composition	According to the instructions	According to the manufacturer's instructions

Table 3 - Summary of evidence by suppository type

Type	Evidence base	Confidence level
Rectal NSAIDs	Systematic reviews and randomized trials	High in NSAID class
Rectal paracetamol	Data are conflicting, inferior to NSAIDs	Moderate
Vaginal CBD	Early studies, quasi-experimental	Low-promising
Herbal formulations	Small studies, inconsistent results	Short

(sources: systematic reviews, RCTs, and observational studies). [28]

Table 4 - Contraindications and precautions

State	Recommendation
Active ulcer and gastrointestinal bleeding	Avoid NSAIDs; consider paracetamol
Severe renal or hepatic impairment	Consult a specialist; avoid or adjust dosages
Pregnancy, 3rd trimester	Avoid most NSAIDs
Anticoagulants	Coordinate with your doctor; use caution with NSAIDs
Allergy to ingredients	Do not use and replace with an alternative

Table 5 - Signs of ineffectiveness and criteria for referral to a specialist

Sign	Action
Pain not relieved by standard therapy	Refer to a gynecologist to rule out secondary dysmenorrhea
New heavy bleeding or breakthrough bleeding	Urgent diagnosis and referral
Unbearable nausea or vomiting	Consider the rectal form and assess dehydration
Recurrent episodes that reduce quality of life	Discussion of hormonal therapy and additional diagnostics

Frequently Asked Questions - Brief and Clear

Question: “Are suppositories more effective than tablets?” Answer: with the same molecule, the effectiveness is comparable; the advantage of suppositories is an alternative route in case of vomiting or poor tolerance of oral administration and sometimes faster absorption. [29]

Question: “Can CBD vaginal suppositories be used instead of NSAIDs?” Answer: These suppositories may reduce symptoms in some women, but the evidence is limited; for severe pain, NSAIDs and hormone therapy, if needed, remain the standard treatment. [30]

Question: "What are the risks of rectal NSAIDs?" Answer: The same as oral NSAIDs: gastrointestinal complications, renal effects, and drug interactions. If there are risks, paracetamol or alternative approaches are used. [31]

Conclusion - practical recommendation

Rectal suppositories containing nonsteroidal medications are a reasonable and effective option for menstrual cramps, especially when the oral route is unavailable. New vaginal formulations, including CBD suppositories and herbal formulas, show potential, but for now they should be considered adjunctive or experimental. Appropriate selection is based on a benefit-risk assessment, exclusion of secondary causes, and discussion of available treatment options with the patient. [32]