Dot40 mg

Dot is indicated for the symptomatic relief of smooth muscle spasm. Evidence and regulatory support vary by indication:

Established/Widely-Used Indications

• Gastrointestinal smooth muscle spasm, including spasm associated with irritable bowel syndrome (IBS) and biliary colic
• Renal colic (ureteric/urinary tract spasm)
• Gynecological smooth muscle spasm, including primary dysmenorrhea (painful menstrual cramps)

Adjunct/Debated Use

• As an adjunct during labor to facilitate cervical dilation, used in some regional obstetric practices. The quality of evidence for this specific use is debated and it is not universally endorsed by all regulatory bodies; use only under direct medical supervision.

Dot relieves spasm-related pain symptomatically but does not treat the underlying cause; a physician should evaluate persistent, severe, or atypical pain.

Each tablet contains Drotaverine Hydrochloride INN 40 mg or 80 mg. Drotaverine is also available as an injectable solution containing Drotaverine Hydrochloride 40 mg/2 mL ampoule for intramuscular or intravenous use, as per locally marketed formulations.

Dot is a musculotropic antispasmodic agent chemically related to papaverine. Unlike anticholinergic antispasmodics, Dot acts directly on smooth muscle to relieve spasm without significant effects on the autonomic nervous system, resulting in a favorable side-effect profile with fewer anticholinergic effects (such as dry mouth or blurred vision).

Dot is widely used across South Asia, Eastern Europe, and the Middle East for the symptomatic management of smooth muscle spasm affecting the gastrointestinal, urinary, and gynecological/obstetric systems.

Dot belongs to the antispasmodic drug class, specifically classified as a musculotropic (direct-acting) smooth muscle relaxant and a selective phosphodiesterase-4 (PDE4) inhibitor. It is chemically an isoquinoline derivative related to papaverine.

Drotaverine exerts its antispasmodic effect by selectively inhibiting phosphodiesterase-4 (PDE4), the enzyme responsible for breaking down cyclic adenosine monophosphate (cAMP) in smooth muscle cells. Inhibition of PDE4 by Drotaverine leads to increased intracellular cAMP concentration, which in turn reduces intracellular calcium levels and produces relaxation of smooth muscle in the gastrointestinal, biliary, urinary, and uterine tracts.

Unlike atropine-like antispasmodics, Drotaverine does not significantly affect autonomic (cholinergic) nerve transmission, so it produces smooth muscle relaxation without prominent anticholinergic side effects.

Pharmacokinetics

• Absorption: Rapidly and almost completely absorbed after oral administration; peak plasma concentration reached within 1-2 hours.
• Metabolism: Extensively metabolized in the liver.
• Elimination: Primarily excreted via urine and bile; elimination half-life is approximately 8-10 hours.

Dot tablets may be taken with or without food, swallowed whole with water. The injectable form of Dot should be administered by a healthcare professional via slow intravenous or intramuscular injection; rapid IV administration should be avoided as it may cause hypotension and collapse.

Dot has the following clinically significant drug interactions:

• Levodopa: Dot may reduce the antiparkinsonian effect of levodopa and can worsen rigidity/tremor; concurrent use should be avoided or closely monitored.
• Antihypertensive agents: Concurrent use with antihypertensives may cause additive hypotensive effects due to the smooth-muscle-relaxant/vasodilatory action of Dot.
• Other antispasmodics and CNS depressants: Concomitant use may theoretically produce additive smooth-muscle-relaxant or sedative effects; use with caution.

Dot is generally well tolerated at recommended doses. Reported side effects include:

• Dizziness
• Hypotension
• Headache
• Palpitations
• Gastrointestinal upset (nausea, constipation)
• Allergic reactions (rare, including rash or angioedema)

Dot should be used during pregnancy only if clearly needed and if the potential benefit justifies the potential risk to the fetus; consult a physician before use. In some regional obstetric practices, Dot is used during labor under direct medical supervision to facilitate cervical dilation; however, the quality of supporting evidence for this specific use is debated, and it is not universally endorsed by all regulatory bodies. Dot should not be used during early pregnancy without medical advice.

Limited data exist on the excretion of Dot in breast milk; use during breastfeeding should be avoided unless a physician determines the benefit outweighs the potential risk to the infant.

Use Dot with caution in patients with hypotension or cardiovascular instability, as its smooth-muscle-relaxant action may lower blood pressure further (see Contraindications for severe cases). Dot provides symptomatic relief of spasm-related pain and is not a substitute for definitive diagnosis or treatment of the underlying cause; patients with severe, persistent, or atypical abdominal or pelvic pain should seek prompt medical evaluation. Use caution when driving or operating machinery until individual response to Dot is known, as dizziness may occur.

Overdose of Dot may cause pronounced hypotension, cardiac conduction disturbances (including AV block), and arrhythmia. If overdose of Dot is suspected, seek immediate medical attention or contact a poison control center/emergency services. Treatment is supportive and symptomatic, to be managed by medical professionals; no specific antidote is available.

Store Dot at room temperature (below 30°C), protected from light and moisture. Keep out of reach of children.

Renal/Hepatic impairment: Use Dot with caution and at reduced doses in mild-to-moderate impairment; avoid in severe hepatic, renal, or cardiac failure (see Contraindications).

Elderly: No specific dose adjustment is generally required, but use with caution given potential for hypotension and cardiovascular comorbidities.

Pediatric: See Pediatric Uses.

Pregnancy/Lactation: See Pregnancy and Lactation.

Dot is generally used for short-term symptomatic relief of acute smooth muscle spasm. Treatment duration should be guided by symptom resolution and a physician's advice; if symptoms persist beyond a few days or worsen, medical review is required to identify and treat the underlying cause.

Antispasmodics; Musculotropic smooth muscle relaxants; Phosphodiesterase-4 (PDE4) inhibitors

Drotaverine selectively inhibits phosphodiesterase-4 (PDE4), increasing intracellular cAMP and reducing intracellular calcium in smooth muscle cells, thereby producing direct relaxation of gastrointestinal, biliary, urinary, and uterine smooth muscle without significant anticholinergic activity.

The safety and efficacy of Dot in children have not been as extensively established as in adults, and use in young children (particularly under 6 years) is generally not recommended without specific pediatric labeling or physician guidance. Where Dot is used in children (typically above 6 years) for indications such as abdominal spasm, lower weight-based doses are used under strict medical supervision. Parents/caregivers should consult a pediatrician before giving Dot to a child.