Ethinylestradiol with drospirenone

How it works

It inhibits ovulation via hypothalamic-pituitary suppression with additional cervical mucus and endometrial effects; drospirenone's anti-mineralocorticoid action counters oestrogen-related fluid retention and its anti-androgen activity benefits acne.

Prescribing in practice

• Drospirenone has potassium-sparing activity, so use caution and consider potassium monitoring with other potassium-raising drugs such as ACE inhibitors, ARBs, potassium-sparing diuretics or NSAIDs.
• Drospirenone-containing pills carry a higher VTE risk than levonorgestrel-containing pills; ensure the woman is counselled accordingly.
• Screen against UKMEC and advise on missed-pill rules and reduced efficacy with enzyme inducers or gastrointestinal upset.

Monitoring

Monitor blood pressure and, where there is concomitant use of potassium-elevating drugs or renal impairment, serum potassium.

Counselling the patient

• Tell your clinician about any blood pressure, kidney or potassium-affecting medicines you take.
• Take at the same time each day and follow missed-pill advice.
• Seek urgent care for symptoms of a clot such as chest pain or calf swelling.

Evidence & guidelines

MHRA and UKMEC guidance address VTE risk by progestogen type, and drospirenone's potassium effect is well established.