The combination of caffeine and birth control pills may generate a few mild side effects, including headaches, jitteriness and insomnia. Caffeine and birth control pills may also interact with other prescribed medications. If you currently take birth control pills and consume excess amounts of caffeine – more than four 8-oz. cups of coffee per day, for example – consider decreasing your intake. Caffeine taken in concert with birth control pills will not decrease the efficacy of the oral contraceptive in the prevention of pregnancy.
Decreased Caffeine Clearance
When you take birth control pills and ingest caffeine, the main impact of the oral contraceptives will be to hold the caffeine in your system longer. Typically the body breaks down caffeine immediately in order to remove it; however birth control pills reduce the speed by which the body performs this action. A 1980 study published in the "Journal of Laboratory and Clinical Medicine" found that women on birth control pills held caffeine in their system nearly four hours longer than women not taking birth control pills.
The most common side effects associated with the combined use of caffeine and birth control pills include headaches, jitteriness, anxiety and an increased heart rate. Other side effects may include trouble falling asleep, as well as drowsiness. The severity of these side effects will depend largely on how much caffeine you ingest.
The combined presence of caffeine and birth control pills in the body may cause adverse reactions with other prescribed medications, including drugs such as Ativan, typically prescribed for anxiety and insomnia. Caffeine and birth control pills may reduce the effectiveness of this medication, so seek clearance from your physician or health care provider before you ingest caffeine, birth control pills and anti-anxiety medications.
On another note, because the combination of caffeine and birth control pills appears to check the diuretic effect of caffeine, this also appears to limit the excretion of vital minerals such as calcium, phosphorus, magnesium, zinc and potassium from the body via the urine. A 2003 study conducted by Brazilian researchers and published in the "Journal of Nutrition" found that the female study participants who ingested caffeine while on birth control pills had significantly less urinary excretion of minerals compared to the participants who were not taking oral contraceptives at the time.
- MedlinePlus: Caffeine in the Diet; David C. Dugdale, III, M.D. et al; May 2009
- "Journal of Laboratory and Clinical Medicine"; Impaired Elimination of Caffeine by Oral Contraceptive Steroids; R.V.Patwardhan; April 1980
- Stanford School of Medicine What Meds: Psychiatric Medications
- "Journal of Nutrition"; Use of Oral Contraceptives Blunts the Calciuric Effect of Caffeine in Young Adult Women; M.A. Ribeiro-Alves et al.; February 2003